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Messages - aREALgod

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4801
The Flood / Re: The first trailer for Star Wars Episode VII is here
« on: November 28, 2014, 11:34:43 AM »
Ew.

I expect it to be a disaster

4802
The Flood / Re: Examples of c00l g0ys, and cool guys
« on: November 28, 2014, 04:30:17 AM »

4803
The Flood / Re: Do you own a gun... Or have shot one?
« on: November 28, 2014, 03:22:42 AM »
Own a Beretta 92FS and have shot multiple weapons. I haven't gone shooting in a while and would love to go again, but prices for ammo in Commiefornia is cock ass bullshit high

4804
And you Europoors make fun of murica freedom USA USA

Enjoy your new overlords, eurofags. They watch you shit and jack off (if you get permission, first)

4805
Serious / Re: Video of 12 year old shot (NSFW)
« on: November 27, 2014, 07:44:32 PM »
I've entirely changed my position after watching the video.

Before, I was totally behind the cops' actions. Kid had a gun, didn't comply with commands, reached for it when told to put his hands up. That's his fault.

After seeing the video, it almost looks like a drive-by shooting. The kid was sitting at a table not doing anything.

>drive-by shooting

Are we watching the same video? I missed the part where they drove off after spraying the area with bullets
The speed at which they pulled their guns and started shooting is what I was talking about. Pull up close to someone, jump out and start shooting? That's something I expect to see in the hood from a gang - not cops.

Right, because that can be deduced from the broken up, fuzzy footage, which does not show how things played out fluidly.

I blame the kid's parents. I mean, what the fuck is a 12 year old doing walking around a park with a REALISTIC looking gun and pointing it at people? I'm surprised some ghetto dude didn't shoot him after freaking out. You're bound to get a response either way, and this one came from the police. I understand why they did what they did. But, let's blame the cops again rather than demand why this kid was unsupervised and not taught how to conduct himself with a mock weapon.

4806
Serious / Re: Video of 12 year old shot (NSFW)
« on: November 27, 2014, 07:37:49 PM »
I've entirely changed my position after watching the video.

Before, I was totally behind the cops' actions. Kid had a gun, didn't comply with commands, reached for it when told to put his hands up. That's his fault.

After seeing the video, it almost looks like a drive-by shooting. The kid was sitting at a table not doing anything.

>drive-by shooting

Are we watching the same video? I missed the part where they drove off after spraying the area with bullets

4807
Serious / Re: Video of 12 year old shot (NSFW)
« on: November 27, 2014, 07:36:34 PM »
inb4ITSCUZHESBLAK

Seeing the video, yeah, I understand the actions of the officer completely. I blame the kid's parent's for not being around, OR teaching him how to conduct himself with a gun, real or fake, in public and in possible presence of an officer.

4808
The Flood / Re: I'm thankful
« on: November 27, 2014, 07:25:09 PM »
Death

4809
The Flood / Re: Legendary Users Private Club
« on: November 27, 2014, 07:20:28 PM »
*puffs cigar*

INDUBITABLY

4810
The Flood / Re: Do you know what I want from all of you?
« on: November 27, 2014, 07:16:57 PM »
The best way to start a second chance is to never ask for one

4811
The Flood / Re: I guess should explain the rumors flying around
« on: November 27, 2014, 04:54:32 AM »
I feel like Dustin is pulling off some class A trolling right now, because there's no possible way he's this autistic.

Right?

4812
The Flood / Re: What kind of car do you have?
« on: November 26, 2014, 02:38:16 PM »
1998 Ford Taurus

But it has a spoiler so its infinitely better than any other cars you guys got

4813
The Flood / Re: Official Wikipedia articles thread
« on: November 26, 2014, 04:11:46 AM »
String theory
From Wikipedia, the free encyclopedia
  (Redirected from String Theory)
For a more accessible and less technical introduction to this topic, see Introduction to M-theory.
String theory
Calabi-Yau-alternate.png
Fundamental objects

    String
    Brane
    D-brane

Perturbative theory

    Bosonic
    Superstring

    Type I
    Type II (IIA / IIB)

    Heterotic (SO(32) · E8×E8)

Non-perturbative results

    S-duality
    T-duality
    M-theory

    AdS/CFT correspondence

Phenomenology

    Phenomenology
    Cosmology

    Landscape

Mathematics

    Mirror symmetry
    Vertex operator algebras

Related concepts[show]
Theorists[show]

    History
    Glossary

    v
    t
    e

In physics, string theory is a theoretical framework in which the point-like particles of particle physics are replaced by one-dimensional objects called strings.[1] String theory aims to explain all types of observed elementary particles using quantum states of these strings. In addition to the particles postulated by the standard model of particle physics, string theory naturally incorporates gravity and so is a candidate for a theory of everything, a self-contained mathematical model that describes all fundamental forces and forms of matter. Besides this potential role, string theory is now widely used as a theoretical tool and has shed light on many aspects of quantum field theory and quantum gravity.[2]

The earliest version of string theory, bosonic string theory, incorporated only the class of particles known as bosons. It was then developed into superstring theory, which posits that a connection – a "supersymmetry" – exists between bosons and the class of particles called fermions. String theory requires the existence of extra spatial dimensions for its mathematical consistency. In realistic physical models constructed from string theory, these extra dimensions are typically compactified to extremely small scales.

String theory was first studied in the late 1960s[3] as a theory of the strong nuclear force before being abandoned in favor of the theory of quantum chromodynamics. Subsequently, it was realized that the very properties that made string theory unsuitable as a theory of nuclear physics made it a promising candidate for a quantum theory of gravity. Five consistent versions of string theory were developed until it was realized in the mid-1990s that they were different limits of a conjectured single 11-dimensional theory now known as M-theory.[4]

Many theoretical physicists, including Stephen Hawking, Edward Witten and Juan Maldacena, believe that string theory is a step towards the correct fundamental description of nature: it accommodates a consistent combination of quantum field theory and general relativity, agrees with insights in quantum gravity (such as the holographic principle and black hole thermodynamics) and has passed many non-trivial checks of its internal consistency.[citation needed] According to Hawking, "M-theory is the only candidate for a complete theory of the universe."[5] Other physicists, such as Richard Feynman,[6][7] Roger Penrose[8] and Sheldon Lee Glashow,[9] have criticized string theory for not providing novel experimental predictions at accessible energy scales.

Contents

    1 Overview
        1.1 Strings
        1.2 Branes
        1.3 Dualities
            1.3.1 S-, T-, and U-duality
            1.3.2 M-theory
        1.4 Extra dimensions
            1.4.1 Number of dimensions
            1.4.2 Compact dimensions
            1.4.3 Brane-world scenario
            1.4.4 Effect of the hidden dimensions
    2 Testability and experimental predictions
        2.1 String harmonics
        2.2 Cosmology
        2.3 Supersymmetry
    3 AdS/CFT correspondence
        3.1 Examples of the correspondence
        3.2 Applications to quantum chromodynamics
        3.3 Applications to condensed matter physics
    4 Connections to mathematics
        4.1 Mirror symmetry
        4.2 Vertex operator algebras
    5 History
        5.1 Early results
        5.2 First superstring revolution
        5.3 Second superstring revolution
    6 Criticisms
        6.1 High energies
        6.2 Number of solutions
        6.3 Background independence
    7 See also
    8 References
    9 Further reading
        9.1 Popular books
            9.1.1 General
            9.1.2 Critical
        9.2 Textbooks
            9.2.1 For physicists
            9.2.2 For mathematicians
        9.3 Online material
    10 External links

Overview
Levels of magnification:
1. Macroscopic level: Matter
2. Molecular level
3. Atomic level: Protons, neutrons, and electrons
4. Subatomic level: Electron
5. Subatomic level: Quarks
6. String level

The starting point for string theory is the idea that the point-like particles of elementary particle physics can also be modeled as one-dimensional objects called strings. According to string theory, strings can oscillate in many ways. On distance scales larger than the string radius, each oscillation mode gives rise to a different species of particle, with its mass, charge, and other properties determined by the string's dynamics. Splitting and recombination of strings correspond to particle emission and absorption, giving rise to the interactions between particles. An analogy for strings' modes of vibration is a guitar string's production of multiple distinct musical notes.[clarification needed] In this analogy, different notes correspond to different particles.

In string theory, one of the modes of oscillation of the string corresponds to a massless, spin-2 particle. Such a particle is called a graviton since it mediates a force which has the properties of gravity. Since string theory is believed to be a mathematically consistent quantum mechanical theory, the existence of this graviton state implies that string theory is a theory of quantum gravity.

String theory includes both open strings, which have two distinct endpoints, and closed strings, which form a complete loop. The two types of string behave in slightly different ways, yielding different particle types. For example, all string theories have closed string graviton modes, but only open strings can correspond to the particles known as photons. Because the two ends of an open string can always meet and connect, forming a closed string, all string theories contain closed strings.

The earliest string model, the bosonic string, incorporated only the class of particles known as bosons. This model describes, at low enough energies, a quantum gravity theory, which also includes (if open strings are incorporated as well) gauge bosons such as the photon. However, this model has problems. What is most significant is that the theory has a fundamental instability, believed to result in the decay (at least partially) of spacetime itself. In addition, as the name implies, the spectrum of particles contains only bosons, particles which, like the photon, obey particular rules of behavior. Roughly speaking, bosons are the constituents of radiation, but not of matter, which is made of fermions. Investigating how a string theory may include fermions led to the invention of supersymmetry, a mathematical relation between bosons and fermions. String theories that include fermionic vibrations are now known as superstring theories; several kinds have been described, but all are now thought to be different limits of a theory called M-theory.

Since string theory incorporates all of the fundamental interactions, including gravity, many physicists hope that it fully describes our universe, making it a theory of everything. One of the goals of current research in string theory is to find a solution of the theory that is quantitatively identical with the standard model, with a small cosmological constant, containing dark matter and a plausible mechanism for cosmic inflation. It is not yet known whether string theory has such a solution, nor is it known how much freedom the theory allows to choose the details.

One of the challenges of string theory is that the full theory does not yet have a satisfactory definition in all circumstances. The scattering of strings is most straightforwardly defined using the techniques of perturbation theory, but it is not known in general how to define string theory nonperturbatively. It is also not clear as to whether there is any principle by which string theory selects its vacuum state, the spacetime configuration that determines the properties of our universe (see string theory landscape).
Strings

The motion of a point-like particle can be described by drawing a graph of its position with respect to time. The resulting picture depicts the worldline of the particle in spacetime. In an analogous way, one can draw a graph depicting the progress of a string as time passes. The string, which looks like a small line by itself, will sweep out a two-dimensional surface known as the worldsheet. The different string modes (giving rise to different particles, such as the photon or graviton) appear as waves on this surface.

A closed string looks like a small loop, so its worldsheet will look like a pipe. An open string looks like a segment with two endpoints, so its worldsheet will look like a strip. In a more mathematical language, these are both Riemann surfaces, the strip having a boundary and the pipe none.
Interaction in the subatomic world: world lines of point-like particles in the Standard Model or a world sheet swept up by closed strings in string theory

Strings can join and split. This is reflected by the form of their worldsheet, or more precisely, by its topology. For example, if a closed string splits, its worldsheet will look like a single pipe splitting into two pipes. This topology is often referred to as a pair of pants (see drawing at right). If a closed string splits and its two parts later reconnect, its worldsheet will look like a single pipe splitting to two and then reconnecting, which also looks like a torus connected to two pipes (one representing the incoming string, and the other representing the outgoing one). An open string doing the same thing will have a worldsheet that looks like an annulus connected to two strips.

In quantum mechanics, one computes the probability for a point particle to propagate from one point to another by summing certain quantities called probability amplitudes. Each amplitude is associated with a different worldline of the particle. This process of summing amplitudes over all possible worldlines is called path integration. In string theory, one computes probabilities in a similar way, by summing quantities associated with the worldsheets joining an initial string configuration to a final configuration. It is in this sense that string theory extends quantum field theory, replacing point particles by strings. As in quantum field theory, the classical behavior of fields is determined by an action functional, which in string theory can be either the Nambu–Goto action or the Polyakov action.
Branes
Main articles: Brane and D-brane

In string theory and related theories such as supergravity theories, a brane is a physical object that generalizes the notion of a point particle to higher dimensions.[10] For example, a point particle can be viewed as a brane of dimension zero, while a string can be viewed as a brane of dimension one. It is also possible to consider higher-dimensional branes. In dimension p, these are called p-branes. The word brane comes from the word "membrane" which refers to a two-dimensional brane.

Branes are dynamical objects which can propagate through spacetime according to the rules of quantum mechanics. They have mass and can have other attributes such as charge. A p-brane sweeps out a (p+1)-dimensional volume in spacetime called its worldvolume. Physicists often study fields analogous to the electromagnetic field which live on the worldvolume of a brane.

In string theory, D-branes are an important class of branes that arise when one considers open strings. As an open string propagates through spacetime, its endpoints are required to lie on a D-brane. The letter "D" in D-brane refers to the fact that we impose a certain mathematical condition on the system known as the Dirichlet boundary condition. The study of D-branes in string theory has led to important results such as the AdS/CFT correspondence, which has shed light on many problems in quantum field theory.

Branes are also frequently studied from a purely mathematical point of view[11] since they are related to subjects such as homological mirror symmetry and noncommutative geometry. Mathematically, branes may be represented as objects of certain categories, such as the derived category of coherent sheaves on a Calabi–Yau manifold, or the Fukaya category.
Dualities

In physics, the term duality refers to a situation where two seemingly different physical systems turn out to be equivalent in a nontrivial way. If two theories are related by a duality, it means that one theory can be transformed in some way so that it ends up looking just like the other theory. The two theories are then said to be dual to one another under the transformation. Put differently, the two theories are mathematically different descriptions of the same phenomena.

In addition to providing a candidate for a theory of everything, string theory provides many examples of dualities between different physical theories and can therefore be used as a tool for understanding the relationships between these theories.[12]
S-, T-, and U-duality
Main articles: S-duality, T-duality and U-duality

These are dualities between string theories which relate seemingly different quantities. Large and small distance scales, as well as strong and weak coupling strengths, are quantities that have always marked very distinct limits of behavior of a physical system in both classical and quantum physics. But strings can obscure the difference between large and small, strong and weak, and this is how these five very different theories end up being related. T-duality relates the large and small distance scales between string theories, whereas S-duality relates strong and weak coupling strengths between string theories. U-duality links T-duality and S-duality.
M-theory
Main article: M-theory

Before the 1990s, string theorists believed there were five distinct superstring theories: type I, type IIA, type IIB, and the two flavors of heterotic string theory (SO(32) and E8×E8). The thinking was that out of these five candidate theories, only one was the actual correct theory of everything, and that theory was the one whose low energy limit, with ten spacetime dimensions compactified down to four, matched the physics observed in our world today. It is now believed that this picture was incorrect and that the five superstring theories are related to one another by the dualities described above. The existence of these dualities suggests that the five string theories are in fact special cases of a more fundamental theory called M-theory.[13]
String theory details by type and number of spacetime dimensions Type    Spacetime dimensions    Details
Bosonic    26    Only bosons, no fermions, meaning only forces, no matter, with both open and closed strings; major flaw: a particle with imaginary mass, called the tachyon, representing an instability in the theory.
I    10    Supersymmetry between forces and matter, with both open and closed strings; no tachyon; gauge group is SO(32)
IIA    10    Supersymmetry between forces and matter, with only closed strings; no tachyon; massless fermions are non-chiral
IIB    10    Supersymmetry between forces and matter, with only closed strings; no tachyon; massless fermions are chiral
HO    10    Supersymmetry between forces and matter, with closed strings only; no tachyon; heterotic, meaning right moving and left moving strings differ; gauge group is SO(32)
HE    10    Supersymmetry between forces and matter, with closed strings only; no tachyon; heterotic; gauge group is E8×E8
Extra dimensions
Number of dimensions

An intriguing feature of string theory is that it predicts extra dimensions. In classical string theory the number of dimensions is not fixed by any consistency criterion. However, to make a consistent quantum theory, string theory is required to live in a spacetime of the so-called "critical dimension": we must have 26 spacetime dimensions for the bosonic string and 10 for the superstring. This is necessary to ensure the vanishing of the conformal anomaly of the worldsheet conformal field theory. Modern understanding indicates that there exist less trivial ways of satisfying this criterion. Cosmological solutions exist in a wider variety of dimensionalities, and these different dimensions are related by dynamical transitions. The dimensions are more precisely different values of the "effective central charge", a count of degrees of freedom that reduces to dimensionality in weakly curved regimes.[14][15]

One such theory is the 11-dimensional M-theory, which requires spacetime to have eleven dimensions,[16] as opposed to the usual three spatial dimensions and the fourth dimension of time. The original string theories from the 1980s describe special cases of M-theory where the eleventh dimension is a very small circle or a line, and if these formulations are considered as fundamental, then string theory requires ten dimensions. But the theory also describes universes like ours, with four observable spacetime dimensions, as well as universes with up to 10 flat space dimensions, and also cases where the position in some of the dimensions is described by a complex number rather than a real number. The notion of spacetime dimension is not fixed in string theory: it is best thought of as different in different circumstances.[17]

Nothing in Maxwell's theory of electromagnetism or Einstein's theory of relativity makes this kind of prediction; these theories require physicists to insert the number of dimensions manually and arbitrarily, and this number is fixed and independent of potential energy. String theory allows one to relate the number of dimensions to scalar potential energy. In technical terms, this happens because a gauge anomaly exists for every separate number of predicted dimensions, and the gauge anomaly can be counteracted by including nontrivial potential energy into equations to solve motion. Furthermore, the absence of potential energy in the "critical dimension" explains why flat spacetime solutions are possible.

This can be better understood by noting that a photon included in a consistent theory (technically, a particle carrying a force related to an unbroken gauge symmetry) must be massless. The mass of the photon that is predicted by string theory depends on the energy of the string mode that represents the photon. This energy includes a contribution from the Casimir effect, namely from quantum fluctuations in the string. The size of this contribution depends on the number of dimensions, since for a larger number of dimensions there are more possible fluctuations in the string position. Therefore, the photon in flat spacetime will be massless—and the theory consistent—only for a particular number of dimensions.[18] When the calculation is done, the critical dimensionality is not four as one may expect (three axes of space and one of time). The subset of X is equal to the relation of photon fluctuations in a linear dimension. Flat space string theories are 26-dimensional in the bosonic case, while superstring and M-theories turn out to involve 10 or 11 dimensions for flat solutions. In bosonic string theories, the 26 dimensions come from the Polyakov equation.[19] Starting from any dimension greater than four, it is necessary to consider how these are reduced to four-dimensional spacetime.
Compact dimensions
Calabi–Yau manifold (3D projection)

Two ways have been proposed to resolve this apparent contradiction. The first is to compactify the extra dimensions; i.e., the 6 or 7 extra dimensions are so small as to be undetectable by present-day experiments.

To retain a high degree of supersymmetry, these compactification spaces must be very special, as reflected in their holonomy. A 6-dimensional manifold must have SU(3) structure, a particular case (torsionless) of this being SU(3) holonomy, making it a Calabi–Yau space, and a 7-dimensional manifold must have G2 structure, with G2 holonomy again being a specific, simple, case. Such spaces have been studied in attempts to relate string theory to the 4-dimensional Standard Model, in part due to the computational simplicity afforded by the assumption of supersymmetry. More recently, progress has been made constructing more realistic compactifications without the degree of symmetry of Calabi–Yau or G2 manifolds.[citation needed]

A standard analogy for this is to consider multidimensional space as a garden hose. If the hose is viewed from sufficient distance, it appears to have only one dimension, its length. Indeed, think of a ball just small enough to enter the hose. Throwing such a ball inside the hose, the ball would move more or less in one dimension; in any experiment we make by throwing such balls in the hose, the only important movement will be one-dimensional, that is, along the hose. However, as one approaches the hose, one discovers that it contains a second dimension, its circumference. Thus, an ant crawling inside it would move in two dimensions (and a fly flying in it would move in three dimensions). This "extra dimension" is only visible within a relatively close range to the hose, or if one "throws in" small enough objects. Similarly, the extra compact dimensions are only "visible" at extremely small distances, or by experimenting with particles with extremely small wavelengths (of the order of the compact dimension's radius), which in quantum mechanics means very high energies (see wave–particle duality).
Brane-world scenario

Another possibility is that we are "stuck" in a 3+1 dimensional (three spatial dimensions plus one time dimension) subspace of the full universe. Properly localized matter and Yang–Mills gauge fields will typically exist if the sub-spacetime is an exceptional set of the larger universe.[20] These "exceptional sets" are ubiquitous in Calabi–Yau n-folds and may be described as subspaces without local deformations, akin to a crease in a sheet of paper or a crack in a crystal, the neighborhood of which is markedly different from the exceptional subspace itself. However, until the work of Randall and Sundrum,[21] it was not known that gravity can be properly localized to a sub-spacetime. In addition, spacetime may be stratified, containing strata of various dimensions, allowing us to inhabit the 3+1-dimensional stratum—such geometries occur naturally in Calabi–Yau compactifications.[22] Such sub-spacetimes are D-branes, hence such models are known as brane-world scenarios.
Effect of the hidden dimensions

In either case, gravity acting in the hidden dimensions affects other non-gravitational forces such as electromagnetism. In fact, Kaluza's early work demonstrated that general relativity in five dimensions actually predicts the existence of electromagnetism. However, because of the nature of Calabi–Yau manifolds, no new forces appear from the small dimensions, but their shape has a profound effect on how the forces between the strings appear in our four-dimensional universe. In principle, therefore, it is possible to deduce the nature of those extra dimensions by requiring consistency with the standard model, but this is not yet a practical possibility. It is also possible to extract information regarding the hidden dimensions by precision tests of gravity, but so far these have only put upper limitations on the size of such hidden dimensions.
Testability and experimental predictions

Although a great deal of recent work has focused on using string theory to construct realistic models of particle physics, several major difficulties complicate efforts to test models based on string theory. The most significant is the extremely small size of the Planck length, which is expected to be close to the string length (the characteristic size of a string, where strings become easily distinguishable from particles). Another issue is the huge number of metastable vacua of string theory, which might be sufficiently diverse to accommodate almost any phenomena we might observe at lower energies.
String harmonics

One unique prediction of string theory is the existence of string harmonics. At sufficiently high energies, the string-like nature of particles would become obvious. There should be heavier copies of all particles, corresponding to higher vibrational harmonics of the string. It is not clear how high these energies are. In most conventional string models, they would be close to the Planck energy, which is 1014 times higher than the energies accessible in the newest particle accelerator, the LHC, making this prediction impossible to test with any particle accelerator in the near future. However, in models with large extra dimensions they could potentially be produced at the LHC, or at energies not far above its reach.
Cosmology

String theory as currently understood makes a series of predictions for the structure of the universe at the largest scales. Many phases in string theory have very large, positive vacuum energy.[23] Regions of the universe that are in such a phase will inflate exponentially rapidly in a process known as eternal inflation. As such, the theory predicts that most of the universe is very rapidly expanding. However, these expanding phases are not stable, and can decay via the nucleation of bubbles of lower vacuum energy. Since our local region of the universe is not very rapidly expanding, string theory predicts we are inside such a bubble. The spatial curvature of the "universe" inside the bubbles that form by this process is negative, a testable prediction.[24] Moreover, other bubbles will eventually form in the parent vacuum outside the bubble and collide with it. These collisions lead to potentially observable imprints on cosmology.[25] However, it is possible that neither of these will be observed if the spatial curvature is too small and the collisions are too rare.

Under certain circumstances, fundamental strings produced at or near the end of inflation can be "stretched" to astronomical proportions. These cosmic strings could be observed in various ways, for instance by their gravitational lensing effects. However, certain field theories also predict cosmic strings arising from topological defects in the field configuration.[26]
Supersymmetry
Main article: Supersymmetry

If confirmed experimentally, supersymmetry is often considered circumstantial evidence, because most consistent string theories are space-time supersymmetric. As with other physical theories, the existence of space-time supersymmetry is a desired feature addressing various issues we encounter in non-supersymmetric theories, like in the Standard Model. However, the absence of supersymmetric particles at energies accessible to the LHC will not actually disprove string theory, since the energy scale at which supersymmetry is broken could be well above the accelerator's range. This would make supersymmetric particles too heavy to be produced in relatively lower energies. On the other hand, there are fully consistent non-supersymmetric string-theories that can also provide phenomenologically relevant predictions.
AdS/CFT correspondence
Main article: AdS/CFT correspondence

The anti-de Sitter/conformal field theory (AdS/CFT) correspondence is a relationship which says that string theory is in certain cases equivalent to a quantum field theory. More precisely, one considers string or M-theory on an anti-de Sitter background. This means that the geometry of spacetime is obtained by perturbing a certain solution of Einstein's equation in the vacuum. In this setting, it is possible to define a notion of "boundary" of spacetime. The AdS/CFT correspondence states that this boundary can be regarded as the "spacetime" for a quantum field theory, and this field theory is equivalent to the bulk gravitational theory in the sense that there is a "dictionary" for translating calculations in one theory into calculations in the other.
Examples of the correspondence

The most famous example of the AdS/CFT correspondence states that Type IIB string theory on the product AdS5 × S5 is equivalent to N = 4 super Yang–Mills theory on the four-dimensional conformal boundary.[27][28][29][30] Another realization of the correspondence states that M-theory on AdS4 × S7 is equivalent to the ABJM superconformal field theory in three dimensions.[31] Yet another realization states that M-theory on AdS7 × S4is equivalent to the so-called (2,0)-theory in six dimensions.[32]
Applications to quantum chromodynamics
Main article: AdS/QCD

Since it relates string theory to ordinary quantum field theory, the AdS/CFT correspondence can be used as a theoretical tool for doing calculations in quantum field theory. For example, the correspondence has been used to study the quark–gluon plasma, an exotic state of matter produced in particle accelerators.

The physics of the quark–gluon plasma is governed by quantum chromodynamics, the fundamental theory of the strong nuclear force, but this theory is mathematically intractable in problems involving the quark–gluon plasma. In order to understand certain properties of the quark–gluon plasma, theorists have therefore made use of the AdS/CFT correspondence. One version of this correspondence relates string theory to a certain supersymmetric gauge theory called N = 4 super Yang–Mills theory. The latter theory provides a good approximation to quantum chromodynamics. One can thus translate problems involving the quark–gluon plasma into problems in string theory which are more tractable. Using these methods, theorists have computed the shear viscosity of the quark–gluon plasma.[33] In 2008, these predictions were confirmed at the Relativistic Heavy Ion Collider at Brookhaven National Laboratory.[34]
Applications to condensed matter physics

In addition, string theory methods have been applied to problems in condensed matter physics. Certain condensed matter systems are difficult to understand using the usual methods of quantum field theory, and the AdS/CFT correspondence may allow physicists to better understand these systems by describing them in the language of string theory. Some success has been achieved in using string theory methods to describe the transition of a superfluid to an insulator.[35][36]
Connections to mathematics

In addition to influencing research in theoretical physics, string theory has stimulated a number of major developments in pure mathematics. Like many developing ideas in theoretical physics, string theory does not at present have a mathematically rigorous formulation in which all of its concepts can be defined precisely. As a result, physicists who study string theory are often guided by physical intuition to conjecture relationships between the seemingly different mathematical structures that are used to formalize different parts of the theory. These conjectures are later proved by mathematicians, and in this way, string theory has served as a source of new ideas in pure mathematics.[37]
Mirror symmetry
Main article: Mirror symmetry (string theory)

One of the ways in which string theory influenced mathematics was through the discovery of mirror symmetry. In string theory, the shape of the unobserved spatial dimensions is typically encoded in mathematical objects called Calabi–Yau manifolds. These are of interest in pure mathematics, and they can be used to construct realistic models of physics from string theory. In the late 1980s, it was noticed that given such a physical model, it is not possible to uniquely reconstruct a corresponding Calabi–Yau manifold. Instead, one finds that there are two Calabi–Yau manifolds that give rise to the same physics. These manifolds are said to be "mirror" to one another. The existence of this mirror symmetry relationship between different Calabi–Yau manifolds has significant mathematical consequences as it allows mathematicians to solve many problems in enumerative algebraic geometry. Today mathematicians are still working to develop a mathematical understanding of mirror symmetry based on physicists' intuition.[38]
Vertex operator algebras
Main articles: Vertex operator algebra and Monstrous moonshine

In addition to mirror symmetry, applications of string theory to pure mathematics include results in the theory of vertex operator algebras. For example, ideas from string theory were used by Richard Borcherds in 1992 to prove the monstrous moonshine conjecture relating the monster group (a construction arising in group theory, a branch of algebra) and modular functions (a class of functions which are important in number theory).[39]
History
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Main article: History of string theory
Early results

Some of the structures reintroduced by string theory arose for the first time much earlier as part of the program of classical unification started by Albert Einstein. The first person to add a fifth dimension to a theory of gravity was Gunnar Nordström in 1914, who noted that gravity in five dimensions describes both gravity and electromagnetism in four. Nordström attempted to unify electromagnetism with his theory of gravitation, which was however superseded by Einstein's general relativity in 1919.[40] Thereafter, German mathematician Theodor Kaluza combined the fifth dimension with general relativity, and only Kaluza is usually credited with the idea.[40] In 1926, the Swedish physicist Oskar Klein gave a physical interpretation of the unobservable extra dimension—it is wrapped into a small circle. Einstein introduced a non-symmetric metric tensor, while much later Brans and Dicke added a scalar component to gravity. These ideas would be revived within string theory, where they are demanded by consistency conditions.

String theory was originally developed during the late 1960s and early 1970s as a never completely successful theory of hadrons, the subatomic particles like the proton and neutron that feel the strong interaction. In the 1960s, Geoffrey Chew and Steven Frautschi discovered that the mesons make families called Regge trajectories with masses related to spins in a way that was later understood by Yoichiro Nambu, Holger Bech Nielsen and Leonard Susskind to be the relationship expected from rotating strings. Chew advocated making a theory for the interactions of these trajectories that did not presume that they were composed of any fundamental particles, but would construct their interactions from self-consistency conditions on the S-matrix. The S-matrix approach was started by Werner Heisenberg in the 1940s as a way of constructing a theory that did not rely on the local notions of space and time, which Heisenberg believed break down at the nuclear scale. While the scale was off by many orders of magnitude, the approach he advocated was ideally suited for a theory of quantum gravity.

Working with experimental data, R. Dolen, D. Horn and C. Schmid[41] developed some sum rules for hadron exchange. When a particle and antiparticle scatter, virtual particles can be exchanged in two qualitatively different ways. In the s-channel, the two particles annihilate to make temporary intermediate states that fall apart into the final state particles. In the t-channel, the particles exchange intermediate states by emission and absorption. In field theory, the two contributions add together, one giving a continuous background contribution, the other giving peaks at certain energies. In the data, it was clear that the peaks were stealing from the background—the authors interpreted this as saying that the t-channel contribution was dual to the s-channel one, meaning both described the whole amplitude and included the other.

The result was widely advertised by Murray Gell-Mann, leading Gabriele Veneziano to construct a scattering amplitude that had the property of Dolen-Horn-Schmid duality, later renamed world-sheet duality. The amplitude needed poles where the particles appear, on straight line trajectories, and there is a special mathematical function whose poles are evenly spaced on half the real line— the Gamma function— which was widely used in Regge theory. By manipulating combinations of Gamma functions, Veneziano was able to find a consistent scattering amplitude with poles on straight lines, with mostly positive residues, which obeyed duality and had the appropriate Regge scaling at high energy. The amplitude could fit near-beam scattering data as well as other Regge type fits, and had a suggestive integral representation that could be used for generalization.

Over the next years, hundreds of physicists worked to complete the bootstrap program for this model, with many surprises. Veneziano himself discovered that for the scattering amplitude to describe the scattering of a particle that appears in the theory, an obvious self-consistency condition, the lightest particle must be a tachyon. Miguel Virasoro and Joel Shapiro found a different amplitude now understood to be that of closed strings, while Ziro Koba and Holger Nielsen generalized Veneziano's integral representation to multiparticle scattering. Veneziano and Sergio Fubini introduced an operator formalism for computing the scattering amplitudes that was a forerunner of world-sheet conformal theory, while Virasoro understood how to remove the poles with wrong-sign residues using a constraint on the states. Claud Lovelace calculated a loop amplitude, and noted that there is an inconsistency unless the dimension of the theory is 26. Charles Thorn, Peter Goddard and Richard Brower went on to prove that there are no wrong-sign propagating states in dimensions less than or equal to 26.

In 1969, Yoichiro Nambu, Holger Bech Nielsen, and Leonard Susskind recognized that the theory could be given a description in space and time in terms of strings. The scattering amplitudes were derived systematically from the action principle by Peter Goddard, Jeffrey Goldstone, Claudio Rebbi, and Charles Thorn, giving a space-time picture to the vertex operators introduced by Veneziano and Fubini and a geometrical interpretation to the Virasoro conditions.

In 1970, Pierre Ramond added fermions to the model, which led him to formulate a two-dimensional supersymmetry to cancel the wrong-sign states. John Schwarz and André Neveu added another sector to the fermi theory a short time later. In the fermion theories, the critical dimension was 10. Stanley Mandelstam formulated a world sheet conformal theory for both the bose and fermi case, giving a two-dimensional field theoretic path-integral to generate the operator formalism. Michio Kaku and Keiji Kikkawa gave a different formulation of the bosonic string, as a string field theory, with infinitely many particle types and with fields taking values not on points, but on loops and curves.

In 1974, Tamiaki Yoneya discovered that all the known string theories included a massless spin-two particle that obeyed the correct Ward identities to be a graviton. John Schwarz and Joel Scherk came to the same conclusion and made the bold leap to suggest that string theory was a theory of gravity, not a theory of hadrons. They reintroduced Kaluza–Klein theory as a way of making sense of the extra dimensions. At the same time, quantum chromodynamics was recognized as the correct theory of hadrons, shifting the attention of physicists and apparently leaving the bootstrap program in the dustbin of history.

String theory eventually made it out of the dustbin, but for the following decade all work on the theory was completely ignored. Still, the theory continued to develop at a steady pace thanks to the work of a handful of devotees. Ferdinando Gliozzi, Joel Scherk, and David Olive realized in 1976 that the original Ramond and Neveu Schwarz-strings were separately inconsistent and needed to be combined. The resulting theory did not have a tachyon, and was proven to have space-time supersymmetry by John Schwarz and Michael Green in 1981. The same year, Alexander Polyakov gave the theory a modern path integral formulation, and went on to develop conformal field theory extensively. In 1979, Daniel Friedan showed that the equations of motions of string theory, which are generalizations of the Einstein equations of General Relativity, emerge from the Renormalization group equations for the two-dimensional field theory. Schwarz and Green discovered T-duality, and constructed two superstring theories—IIA and IIB related by T-duality, and type I theories with open strings. The consistency conditions had been so strong, that the entire theory was nearly uniquely determined, with only a few discrete choices.
First superstring revolution

In the early 1980s, Edward Witten discovered that most theories of quantum gravity could not accommodate chiral fermions like the neutrino. This led him, in collaboration with Luis Alvarez-Gaumé to study violations of the conservation laws in gravity theories with anomalies, concluding that type I string theories were inconsistent. Green and Schwarz discovered a contribution to the anomaly that Witten and Alvarez-Gaumé had missed, which restricted the gauge group of the type I string theory to be SO(32). In coming to understand this calculation, Edward Witten became convinced that string theory was truly a consistent theory of gravity, and he became a high-profile advocate. Following Witten's lead, between 1984 and 1986, hundreds of physicists started to work in this field, and this is sometimes called the first superstring revolution.

During this period, David Gross, Jeffrey Harvey, Emil Martinec, and Ryan Rohm discovered heterotic strings. The gauge group of these closed strings was two copies of E8, and either copy could easily and naturally include the standard model. Philip Candelas, Gary Horowitz, Andrew Strominger and Edward Witten found that the Calabi–Yau manifolds are the compactifications that preserve a realistic amount of supersymmetry, while Lance Dixon and others worked out the physical properties of orbifolds, distinctive geometrical singularities allowed in string theory. Cumrun Vafa generalized T-duality from circles to arbitrary manifolds, creating the mathematical field of mirror symmetry. Daniel Friedan, Emil Martinec and Stephen Shenker further developed the covariant quantization of the superstring using conformal field theory techniques. David Gross and Vipul Periwal discovered that string perturbation theory was divergent. Stephen Shenker showed it diverged much faster than in field theory suggesting that new non-perturbative objects were missing.

In the 1990s, Joseph Polchinski discovered that the theory requires higher-dimensional objects, called D-branes and identified these with the black-hole solutions of supergravity. These were understood to be the new objects suggested by the perturbative divergences, and they opened up a new field with rich mathematical structure. It quickly became clear that D-branes and other p-branes, not just strings, formed the matter content of the string theories, and the physical interpretation of the strings and branes was revealed—they are a type of black hole. Leonard Susskind had incorporated the holographic principle of Gerardus 't Hooft into string theory, identifying the long highly excited string states with ordinary thermal black hole states. As suggested by 't Hooft, the fluctuations of the black hole horizon, the world-sheet or world-volume theory, describes not only the degrees of freedom of the black hole, but all nearby objects too.
Second superstring revolution
Edward Witten

In 1995, at the annual conference of string theorists at the University of Southern California (USC), Edward Witten gave a speech on string theory that in essence united the five string theories that existed at the time, and giving birth to a new 11-dimensional theory called M-theory. M-theory was also foreshadowed in the work of Paul Townsend at approximately the same time. The flurry of activity that began at this time is sometimes called the second superstring revolution.

During this period, Tom Banks, Willy Fischler, Stephen Shenker and Leonard Susskind formulated matrix theory, a full holographic description of M-theory using IIA D0 branes.[42] This was the first definition of string theory that was fully non-perturbative and a concrete mathematical realization of the holographic principle. It is an example of a gauge-gravity duality and is now understood to be a special case of the AdS/CFT correspondence. Andrew Strominger and Cumrun Vafa calculated the entropy of certain configurations of D-branes and found agreement with the semi-classical answer for extreme charged black holes. Petr Hořava and Witten found the eleven-dimensional formulation of the heterotic string theories, showing that orbifolds solve the chirality problem. Witten noted that the effective description of the physics of D-branes at low energies is by a supersymmetric gauge theory, and found geometrical interpretations of mathematical structures in gauge theory that he and Nathan Seiberg had earlier discovered in terms of the location of the branes.

In 1997, Juan Maldacena noted that the low energy excitations of a theory near a black hole consist of objects close to the horizon, which for extreme charged black holes looks like an anti-de Sitter space. He noted that in this limit the gauge theory describes the string excitations near the branes. So he hypothesized that string theory on a near-horizon extreme-charged black-hole geometry, an anti-deSitter space times a sphere with flux, is equally well described by the low-energy limiting gauge theory, the N = 4 supersymmetric Yang–Mills theory. This hypothesis, which is called the AdS/CFT correspondence, was further developed by Steven Gubser, Igor Klebanov and Alexander Polyakov, and by Edward Witten, and it is now well-accepted. It is a concrete realization of the holographic principle, which has far-reaching implications for black holes, locality and information in physics, as well as the nature of the gravitational interaction. Through this relationship, string theory has been shown to be related to gauge theories like quantum chromodynamics and this has led to more quantitative understanding of the behavior of hadrons, bringing string theory back to its roots.
Criticisms

Some critics of string theory say that it is a failure as a theory of everything.[43][44][45][46][47][48] Notable critics include Peter Woit, Lee Smolin, Philip Warren Anderson,[49] Sheldon Glashow,[50] Lawrence Krauss,[51] Carlo Rovelli[52] and Bert Schroer.[53] Some common criticisms include:

    Very high energies needed to test quantum gravity.
    Lack of uniqueness of predictions due to the large number of solutions.
    Lack of background independence.

High energies

It is widely believed that any theory of quantum gravity would require extremely high energies to probe directly, higher by orders of magnitude than those that current experiments such as the Large Hadron Collider[54] can attain. This is because strings themselves are expected to be only slightly larger than the Planck length, which is twenty orders of magnitude smaller than the radius of a proton, and high energies are required to probe small length scales. Generally speaking, quantum gravity is difficult to test because gravity is much weaker than the other forces, and because quantum effects are controlled by Planck's constant h, a very small quantity. As a result, the effects of quantum gravity are extremely weak.
Number of solutions

String theory as it is currently understood has a huge number of solutions, called string vacua,[23] and these vacua might be sufficiently diverse to accommodate almost any phenomena we might observe at lower energies.

The vacuum structure of the theory, called the string theory landscape (or the anthropic portion of string theory vacua), is not well understood. String theory contains an infinite number of distinct meta-stable vacua, and perhaps 10520 of these or more correspond to a universe roughly similar to ours—with four dimensions, a high planck scale, gauge groups, and chiral fermions. Each of these corresponds to a different possible universe, with a different collection of particles and forces.[23] What principle, if any, can be used to select among these vacua is an open issue. While there are no continuous parameters in the theory, there is a very large set of possible universes, which may be radically different from each other. It is also suggested that the landscape is surrounded by an even more vast swampland of consistent-looking semiclassical effective field theories, which are actually inconsistent.[55]

Some physicists believe this is a good thing, because it may allow a natural anthropic explanation of the observed values of physical constants, in particular the small value of the cosmological constant.[56][57] The argument is that most universes contain values for physical constants that do not lead to habitable universes (at least for humans), and so we happen to live in the "friendliest" universe. This principle is already employed to explain the existence of life on earth as the result of a life-friendly orbit around the medium-sized sun among an infinite number of possible orbits (as well as a relatively stable location in the galaxy).
Background independence
See also: Background independence

A separate and older criticism of string theory is that it is background-dependent—string theory describes perturbative expansions about fixed spacetime backgrounds which means that mathematical calculations in the theory rely on preselecting a background as a starting point. This is because, like many quantum field theories, much of string theory is still only formulated perturbatively, as a divergent series of approximations.[citation needed]

Although the theory, defined as a perturbative expansion on a fixed background, is not background independent, it has some features that suggest non-perturbative approaches would be background-independent—topology change is an established process in string theory, and the exchange of gravitons is equivalent to a change in the background. Since there are dynamic corrections to the background spacetime in the perturbative theory, one would expect spacetime to be dynamic in the nonperturbative theory as well since they would have to predict the same spacetime.[citation needed]

This criticism has been addressed to some extent by the AdS/CFT duality, which is believed to provide a full, non-perturbative definition of string theory in spacetimes with anti-de Sitter space asymptotics. Nevertheless, a non-perturbative definition of the theory in arbitrary spacetime backgrounds is still lacking. Some hope that M-theory, or a non-perturbative treatment of string theory (such as "background independent open string field theory") will have a background-independent formulation.[citation needed]
See also

    Conformal field theory
    Glossary of string theory
    List of string theory topics
    Loop quantum gravity
    Supergravity
    Supersymmetry

References

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    6d (2,0)-supersymmetric QFT in nLab
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    "there ain't no experiment that could be done nor is there any observation that could be made that would say, `You guys are wrong.' The theory is safe, permanently safe" NOVA interview
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    Schroer, B. (2008) String theory and the crisis of particle physics II or the ascent of metaphoric arguments, arXiv:0805.1911
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    Arkani-Hamed, N.; Dimopoulos, S. and Kachru, S. Predictive Landscapes and New Physics at a TeV, arXiv:hep-th/0501082, SLAC-PUB-10928, HUTP-05-A0001, SU-ITP-04-44, January 2005
    Susskind, L. The Anthropic Landscape of String Theory, arXiv:hep-th/0302219, February 2003

Further reading
Popular books
General

    Davies, Paul; Julian R. Brown (Eds.) (1992). Superstrings: A Theory of Everything?. Cambridge: Cambridge University Press. ISBN 0-521-43775-X.
    Greene, Brian (2003). The Elegant Universe: Superstrings, Hidden Dimensions, and the Quest for the Ultimate Theory. New York: W.W. Norton & Company. ISBN 0-393-05858-1.
    Greene, Brian (2004). The Fabric of the Cosmos: Space, Time, and the Texture of Reality. New York: Alfred A. Knopf. ISBN 0-375-41288-3.
    Kaku, Michio (1994). Hyperspace: A Scientific Odyssey Through Parallel Universes, Time Warps, and the Tenth Dimension. Oxford: Oxford University Press. ISBN 0-19-508514-0.
    Musser, George (2008). The Complete Idiot's Guide to String Theory. Indianapolis: Alpha. ISBN 978-1-59257-702-6.
    Randall, Lisa (2005). Warped Passages: Unraveling the Mysteries of the Universe's Hidden Dimensions. New York: Ecco Press. ISBN 0-06-053108-8.
    Susskind, Leonard (2006). The Cosmic Landscape: String Theory and the Illusion of Intelligent Design. New York: Hachette Book Group/Back Bay Books. ISBN 0-316-01333-1.
    Yau, Shing-Tung; Nadis, Steve (2010). The Shape of Inner Space: String Theory and the Geometry of the Universe's Hidden Dimensions. Basic Books. ISBN 978-0-465-02023-2.

Critical

    Penrose, Roger (2005). The Road to Reality: A Complete Guide to the Laws of the Universe. Knopf. ISBN 0-679-45443-8.
    Smolin, Lee (2006). The Trouble with Physics: The Rise of String Theory, the Fall of a Science, and What Comes Next. New York: Houghton Mifflin Co. ISBN 0-618-55105-0.
    Woit, Peter (2006). Not Even Wrong: The Failure of String Theory And the Search for Unity in Physical Law. London: Jonathan Cape &: New York: Basic Books. ISBN 978-0-465-09275-8.

Textbooks
For physicists

    Becker, Katrin, Becker, Melanie, and Schwarz, John (2007) String Theory and M-Theory: A Modern Introduction . Cambridge University Press. ISBN 0-521-86069-5
    Dine, Michael (2007) Supersymmetry and String Theory: Beyond the Standard Model. Cambridge University Press. ISBN 0-521-85841-0.
    Kiritsis, Elias (2007) String Theory in a Nutshell. Princeton University Press. ISBN 978-0-691-12230-4.
    Michael Green, John H. Schwarz and Edward Witten (1987) Superstring theory. Cambridge University Press.
        Vol. 1: Introduction. ISBN 0-521-35752-7.
        Vol. 2: Loop amplitudes, anomalies and phenomenology. ISBN 0-521-35753-5.
    Johnson, Clifford (2003). D-branes. Cambridge: Cambridge University Press. ISBN 0-521-80912-6.
    Polchinski, Joseph (1998) String theory. Cambridge University Press.
        Vol. 1: An Introduction to the Bosonic String. ISBN 0-521-63303-6.
        Vol. 2: Superstring Theory and Beyond. ISBN 0-521-63304-4.
    Szabo, Richard J. (2007) An Introduction to String Theory and D-brane Dynamics. Imperial College Press. ISBN 978-1-86094-427-7.
    Zwiebach, Barton (2004) A First Course in String Theory. Cambridge University Press. ISBN 0-521-83143-1.

For mathematicians

    Aspinwall, Paul; Bridgeland, Tom; Craw, Alastair; Douglas, Michael; Gross, Mark; Kapustin, Anton; Moore, Gregory; Segal, Graeme; Szendröi, Balázs; Wilson, P.M.H., eds. (2009). Dirichlet Branes and Mirror Symmetry. American Mathematical Society.
    Deligne, Pierre; Etingof, Pavel; Freed, Daniel; Jeffery, Lisa; Kazhdan, David; Morgan, John; Morrison, David; Witten, Edward, eds. (1999). Quantum Fields and Strings: A Course for Mathematicians. American Mathematical Society. ISBN 0821820125.
    Hori, Kentaro; Katz, Sheldon; Klemm, Albrecht; Pandharipande, Rahul; Thomas, Richard; Vafa, Cumrun; Vakil, Ravi; Zaslow, Eric, eds. (2003). Mirror Symmetry. American Mathematical Society. ISBN 0821829556.

Online material

    Klebanov, Igor and Maldacena, Juan (January 2009). "Solving Quantum Field Theories via Curved Spacetimes". Physics Today.
    Schwarz, John H. (2000). "Introduction to Superstring Theory". arXiv:hep-ex/0008017 [hep-ex].
    Witten, Edward (June 2002). "The Universe on a String" (PDF). Astronomy Magazine. Retrieved December 19, 2005.
    Witten, Edward (1998). "Duality, Spacetime and Quantum Mechanics". Kavli Institute for Theoretical Physics. Retrieved December 16, 2005.
    Woit, Peter (2002). "Is string theory even wrong?". American Scientist. Retrieved December 16, 2005.

External links
   Look up string theory in Wiktionary, the free dictionary.
   Wikimedia Commons has media related to String theory.

    Why String Theory—An introduction to string theory.
    Dialogue on the Foundations of String Theory at MathPages
    Superstrings! String Theory Home Page—Online tutorial
    A Layman’s Guide to String Theory—An explanation for the layperson
    Not Even Wrong—A blog critical of string theory
    The Official String Theory Web Site
    The Elegant Universe—A three-hour miniseries with Brian Greene by NOVA (original PBS Broadcast Dates: October 28, 8–10 p.m. and November 4, 8–9 p.m., 2003). Various images, texts, videos and animations explaining string theory.
    Beyond String Theory—A project by a string physicist explaining aspects of string theory to a broad audience
    String Theory and M-Theory a serious but amusing lecture with not to complicated math and not too advanced physics, by Prof. Leonard Susskind at Stanford University

4814
The Flood / Re: Official Wikipedia articles thread
« on: November 26, 2014, 04:10:57 AM »
Mike Quinn
From Wikipedia, the free encyclopedia
For other people named Mike Quinn, see Mike Quinn (disambiguation).
Mike Quinn White American male holding a football in throwing position, wearing a silver helmet with a star on the sides and a white jersey and silver pants
Quinn as a member of the Dallas Cowboys
Quarterback
Personal information
Date of birth: April 15, 1974 (age 40)
Place of birth: Las Vegas, Nevada
Height: 6 ft 4 in (1.93 m)    Weight: 215 lb (98 kg)
Career information
College: Stephen F. Austin State University
Undrafted in 1997
Debuted in 1997 for the Pittsburgh Steelers
Last played in 2006 for the Winnipeg Blue Bombers
Career history

    Pittsburgh Steelers (1997)
    Rhein Fire (1998)
    Indianapolis Colts (1998)
    Dallas Cowboys (1998–1999)
    Miami Dolphins (2000–2001)
    Houston Texans (2002–2003)
    Denver Broncos (2004)*
    Pittsburgh Steelers (2004)*
    Montreal Alouettes (2005)*
    Winnipeg Blue Bombers (2006)

    *Offseason and/or practice squad member only

Career highlights and awards

    All-NFL Europe (1998)
    World Bowl champion (VI)

Career NFL statistics as of 2003
TDs–INTs    1–0
Passing yards    20
QB rating    85.4
Stats at NFL.com
Career CFL statistics as of 2006
TDs–INTs    3–5
Passing yards    355
QB rating    55.8
Stats at CFL.ca

Michael Patrick Quinn (born April 15, 1974 in Las Vegas, Nevada) is a former professional gridiron football quarterback. He was signed by the Pittsburgh Steelers as an undrafted free agent in 1997 and was also a member of the Rhein Fire, Indianapolis Colts, Dallas Cowboys, Miami Dolphins, Houston Texans, Denver Broncos, Montreal Alouettes and Winnipeg Blue Bombers. He played college football at Stephen F. Austin State University.

Quinn attended Lee High School in Houston, Texas and Stephen F. Austin State University.[1] He started playing football in high school and played at university, where he started for one season, his senior season. After he went undrafted in the 1997 NFL Draft he signed with the Pittsburgh Steelers. With Pittsburgh, he ended up making the roster as the third–string quarterback. Following the season, he was allocated to the Rhein Fire, whom he led to the championship game. He spent 1998 and 1999 as a backup for the Indianapolis Colts and Dallas Cowboys before signing with the Miami Dolphins. Quinn spent two seasons backing up for the Dolphins. In 2002, he was one of the first group of players signed by the National Football League (NFL) expansion franchise, the Houston Texans. As he had done for the previous years in his career, Quinn spent two seasons as a backup for the new franchise. The final year of his NFL career was spent with the Denver Broncos in training camp and with the Steelers' practice squad. After going unsigned, Quinn signed with the Montreal Alouettes joining their practice squad in August 2005, leaving the team after the season. Quinn joined another Canadian team, the Winnipeg Blue Bombers in March 2006 but after receiving playing time in a backup role he was released in August.

Contents

    1 Personal
    2 College career
    3 Professional career
        3.1 1997–2003
        3.2 2004–2006
    4 References

Personal

Quinn attended Robert E. Lee High School in Houston, Texas. He was named to the state All-Star team during his tenure. Currently, he and his wife, Jennifer, live in Houston, Texas. At Stephen F. Austin, he majored in accounting.
College career

On November 12, 1995 in a game against Southwest Texas State, Quinn came into the game for starting quarterback James Ritchey and threw three touchdown passes.[2]

In the game against Samford on October 27, 1996, Quinn led Stephen F. Austin to a 43–14 win after throwing a touchdown pass to Chris Jefferson at the end of the first half. SFA held the lead for the rest of the game.[3] Against McNeese State on November 3, Quinn led a come from behind win for SFA by throwing two touchdowns to Mikhael Ricks in the fourth quarter.[4] The next week, Quinn threw for 283 yards and threw four touchdown passes to lead Stephen F. Austin to another win making them 7–2.[5] However, against Southwest Texas State on November 17, Quinn threw 23 incomplete passes.[6]
Professional career
1997–2003

Quinn signed with the Pittsburgh Steelers as an undrafted free agent following the 1997 NFL Draft.[7] Quinn entered training camp behind Kordell Stewart, Mike Tomczak and Jim Miller on the depth chart, but after training camp Quinn had beaten out Miller and became the team's third-string quarterback.[8] He saw his only game action[9] on November 9 against the Baltimore Ravens, throwing for 10 yards on one completion.[10] Following the 1997 season, the Steelers allocated Quinn to play in NFL Europe,[11] he later agreed to play for the Rhein Fire.[12] In his second game with the Fire on April 12, Quinn completed 13 of 21 passes for 194 yards. He also completed two touchdown passes.[13] With Quinn as the starting quarterback, the Fire played in the World Bowl. However, Quinn was hampered by a sprained ankle and could not play in the game.[14][15] He returned to the Steelers after the NFL Europe season but was waived on August 31.[16]

After being waived by Pittsburgh, Quinn was claimed off waivers by the Indianapolis Colts on September 1. To make room for Quinn the Colts had to release Jim Miller, who had lost a roster spot on the Steelers to Quinn a year earlier.[17] However, after signing Doug Nussmeier, the Colts waived Quinn.[18]

The Dallas Cowboys, who were unsuccessful claiming Quinn 10 days earlier,[17] claimed him after he was waived by the Colts.[19] In Dallas, Quinn became the Cowboys second-string quarterback after Troy Aikman was injured and Jason Garrett became the starter.[20] He played in three games for the Cowboys in 1998, completing one pass for 10 yards. In 1999, Quinn did not play in a game for Dallas.[9] During the 2000 off–season, Garrett signed as a free agent with the New York Giants[21] and quarterback Paul Justin was signed by Dallas to compete for the backup spot with Quinn.[22] He was released on May 5, 2000.[23]

Quinn signed with the Miami Dolphins on May 23, 2000.[24] On November 6, Quinn threw a touchdown pass to Deon Dyer[25] but was waived by the Dolphins on November 10,[26] only to be re-signed four days later.[27] In the 2001 preseason, Quinn sprained a joint in his shoulder and was waived/injured.[28] He was released from injured reserve with an injury settlement on September 6.[29]

The Houston Texans, the newest franchise in the NFL, signed Quinn to a reserve/future contract on December 30, 2001.[30] Following the 2002 NFL Draft in which the Texans drafted quarterback David Carr with their first ever pick, Quinn became the backup.[31] Quinn and Tony Banks ended up winning the backup jobs to Carr[32] over Kent Graham and Ben Sankey.[33] Banks was second–string with Quinn being the third–string quarterback.[34] The Texans waived Quinn during final cuts on August 25, 2003. He was the final member of the Texans first signings still on the team.[35] He was re-signed to the practice squad on November 17 after David Carr suffered a sprained right shoulder.[36] However, when Banks also became injured, Quinn was signed from the practice squad to back up the now healthy Carr and rookie Dave Ragone.[37]
2004–2006

The Denver Broncos signed Quinn as an unrestricted free agent in March 2004.[38] At the end of training camp, Quinn was released by the Broncos.[39]

Quinn was re-signed by the Steelers on September 22 and assigned to their practice squad.[40] He was released from the practice squad on November 10.[41]

Quinn was signed to the Montreal Alouettes practice roster on August 29, 2005.[42]

The Winnipeg Blue Bombers signed Quinn on March 22, 2006 joining quarterbacks Tee Martin, Russ Michna and Kevin Glenn on Winnipeg's roster.[43] In his CFL preseason debut against the Montreal Alouettes on June 2, Quinn threw a 24 yard touchdown pass to Quentin McCord however the Blue Bombers lost 25–24.[44] After making the team out of training camp, Quinn injured his sternum and shoulder which caused him to miss three weeks.[45] In his first week back with Winnipeg, Quinn was forced into the starting role after Kevin Glenn suffered a knee injury.[46] However, a string of poor performances which included an interception in the end zone while Winnipeg was in field goal position led to his release on August 28.[47]
References

    Brown, Chip. "TEXANS SIDELINE." The Dallas Morning News. September 4, 2002. Retrieved on February 5, 2011. "Mike Quinn: A product of Robert E. Lee High School in Houston and Stephen F. Austin,"
    "Stephen F. Austin handles SWT". Austin American-Statesman. November 12, 1995. Retrieved 2009-09-19.
    "Marshall toughens in Second Half". South Florida Sun-Sentinel. October 27, 1996. Retrieved 2009-09-19.
    "SFA rallies by McNeese". Baton Rouge Advocate. November 3, 1996. Retrieved 2009-09-19.
    Wire, From (November 10, 1996). "Austin College upsets Howard Payne". Dallas Morning News. Retrieved 2009-09-19.
    Date, BILL MARTIN (November 17, 1996). "Mathis explodes for 310". Austin American-Statesman. Retrieved 2009-09-19.
    "Why ask why? Questions linger after Woodson's Steelers career apparently ends". Pittsburgh Post-Gazette. April 22, 1997. Retrieved 2009-09-19.
    "Steelers cut Miller Series: NFL". The St. Petersburg Times. August 24, 1997. Retrieved 2009-09-19.
    "Mike Quinn". NFL.com. Retrieved 2009-09-19.
    "Box Score: Baltimore Ravens at Pittsburgh Steelers". Sports Illustrated. November 9, 1997. Retrieved 2009-09-19.
    "NFL Europe Allocation Draft". USA Today. February 18, 1998. Retrieved 2009-09-19.
    "Steelers expecting to lose Thigpen, Jackson likely out, too". Pittsburgh Post-Gazette. February 14, 1998. Retrieved 2009-09-19.
    "It's all up to Elway, even deal with 49ers". San Diego Union-Tribune. April 12, 1998. Retrieved 2009-09-19.
    "World Bowl May Be Decided by Second Fiddles". The Washington Post. June 14, 1998. Retrieved 2009-09-19.
    "Sports Briefly Substitute QB helps Fire win World Bowl". Fort Worth Star Telegram. June 15, 1998. Retrieved 2009-09-19.
    "Transactions". The New York Times. August 31, 1998. Retrieved 2009-09-19.
    "Quick slants". Pittsburgh Post-Gazette. September 1, 1998. Retrieved 2009-09-19.
    "Transactions". The Hartford Courant. September 10, 1998. Retrieved 2009-09-19.
    "The slighted Quinn". Pittsburgh Post-Gazette. Retrieved 2009-09-19.[dead link]
    Smith, Timothy W. (September 16, 1998). "Cowboys Rallying Round Garrett". The New York Times. Retrieved 2009-09-19.
    Taylor, Jean-Jacques (February 23, 2000). "Garrett leaving Cowboys to become NY Giants' backup QB". Dallas Morning News. Retrieved 2009-09-19.
    Moore, David (March 29, 2000). "Cowboys near deal with backup QB Justin". Dallas Morning News. Retrieved 2009-09-19.
    "Cowboys release QB Mike Quinn". Associated Press. May 5, 2000. Retrieved 2009-09-19.
    "Dolphins sign veteran QB Quinn". Associated Press. May 23, 2000. Retrieved 2009-09-19.

4815
The Flood / Re: Cheat... I'm done...
« on: November 26, 2014, 12:07:53 AM »
plz

Please
From Wikipedia, the free encyclopedia
   Look up please in Wiktionary, the free dictionary.

Please may refer to:

    "Please", an expression of request

Music

    Please (Pet Shop Boys album), 1986
    Please (Matt Nathanson album), 1993
    "Please" (Toni Braxton song), 2005
    "Please" (Robin Gibb song), 2003
    "Please" (The Kinleys song), 1997
    "Please" (U2 song), 1997
    "Please (You Got That...)", a 1993 song by INXS

    "Please", a song by The Apples in Stereo from Velocity of Sound
    "Please", a song by John Cale from Vintage Violence
    "Please", a song by Lamb from Between Darkness and Wonder
    "Please", a song by Tom McRae from The Alphabet of Hurricanes
    "Please", a song by Nine Inch Nails from The Fragile
    "Please", a song by Paul Hartnoll from The Ideal Condition
    "Please", a song by Chris Isaak from Speak of the Devil
    "Please", a song from the 1989 musical Miss Saigon
    "Please", a song by Pam Tillis from the album Thunder & Roses
    "Please", a song by Staind from Chapter V

    "Please", a song by Ludo

Other uses

    Please Teacher!, an anime series
    PLEASE, a keyword in the INTERCAL programming language

See also

    "Please, Please", a song by McFly
    Please, Please, Please (disambiguation)

4816
The Flood / Re: Cheat... I'm done...
« on: November 26, 2014, 12:02:11 AM »
World War II
From Wikipedia, the free encyclopedia
"The Second World War" and "WWII" redirect here. For other uses, see The Second World War (disambiguation) and WWII (disambiguation).
Page semi-protected
World War II
Infobox collage for WWII.PNG
Clockwise from top left: Chinese forces in the Battle of Wanjialing, Australian 25-pounder guns during the First Battle of El Alamein, German Stuka dive bombers on the Eastern Front in December 1943, a US naval force in the Lingayen Gulf, Wilhelm Keitel signing the German Instrument of Surrender, Soviet troops in the Battle of Stalingrad
Date    1 September 1939 – 2 September 1945 (6 years, 1 day)[a]
Location    Europe, Pacific, Atlantic, South-East Asia, China, Middle East, Mediterranean, North Africa and Horn of Africa, briefly North and South America
Result    Allied victory

    Collapse of the Third Reich
    Fall of Japanese and Italian Empires
    Creation of the United Nations
    Emergence of the United States and the Soviet Union as superpowers
    Beginning of the Cold War (more...).

Belligerents
Allies    Axis
Commanders and leaders
Allied leaders

Soviet Union Joseph Stalin
United States Franklin D. Roosevelt
United Kingdom Winston Churchill
Republic of China (1912–49) Chiang Kai-shek
   Axis leaders

Nazi Germany Adolf Hitler
Empire of Japan Hirohito
Kingdom of Italy Benito Mussolini
Casualties and losses
Military dead:
Over 16,000,000
Civilian dead:
Over 45,000,000
Total dead:
Over 61,000,000 (1937–45)
...further details    Military dead:
Over 8,000,000
Civilian dead:
Over 4,000,000
Total dead:
Over 12,000,000 (1937–45)
...further details
[show]

    v
    t
    e

Campaigns of World War II
World War II
Alphabetical indices

    A B C D E F G H I J K L M
    N O P Q R S T U V W X Y Z
    0-9

Navigation

        Campaigns
        Countries
        Equipment
        Lists
        Outline
        Timeline
        Portal
        Category

    v
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World War II (WWII or WW2), also known as the Second World War, was a global war that lasted from 1939 to 1945, though related conflicts began earlier. It involved the vast majority of the world's nations—including all of the great powers—eventually forming two opposing military alliances: the Allies and the Axis. It was the most widespread war in history, and directly involved more than 100 million people from over 30 countries. In a state of "total war", the major participants threw their entire economic, industrial and scientific capabilities behind the war effort, erasing the distinction between civilian and military resources. Marked by mass deaths of civilians, including the Holocaust (during which approximately 11 million people were killed)[1][2] and the strategic bombing of industrial and population centres (during which approximately one million people were killed, including the use of two nuclear weapons in combat),[3] it resulted in an estimated 50 million to 85 million fatalities. These made World War II the deadliest conflict in human history.[4]

The Empire of Japan aimed to dominate Asia and the Pacific and was already at war with the Republic of China in 1937,[5] but the world war is generally said to have begun on 1 September 1939[6] with the invasion of Poland by Germany and subsequent declarations of war on Germany by France and the United Kingdom. From late 1939 to early 1941, in a series of campaigns and treaties, Germany conquered or controlled much of continental Europe, and formed the Axis alliance with Italy and Japan. Following the Molotov–Ribbentrop Pact, Germany and the Soviet Union partitioned and annexed territories of their European neighbours, including Poland, Finland and the Baltic states. The United Kingdom and the British Commonwealth were the only Allied forces continuing the fight against the Axis, with campaigns in North Africa and the Horn of Africa as well as the long-running Battle of the Atlantic. In June 1941, the European Axis powers launched an invasion of the Soviet Union, opening the largest land theatre of war in history, which trapped the major part of the Axis' military forces into a War of Attrition. In December 1941, Japan attacked the United States and European territories in the Pacific Ocean, and quickly conquered much of the Western Pacific.

The Axis advance halted in 1942 when Japan lost the critical Battle of Midway, near Hawaii, and Germany was defeated in North Africa and then, decisively, at Stalingrad in the Soviet Union. In 1943, with a series of German defeats on the Eastern Front, the Allied invasion of Italy which brought about Italian surrender, and Allied victories in the Pacific, the Axis lost the initiative and undertook strategic retreat on all fronts. In 1944, the Western Allies invaded France, while the Soviet Union regained all of its territorial losses and invaded Germany and its allies. During 1944 and 1945 the Japanese suffered major reverses in mainland Asia in South Central China and Burma, while the Allies crippled the Japanese Navy and captured key Western Pacific islands.

The war in Europe ended with an invasion of Germany by the Western Allies and the Soviet Union culminating in the capture of Berlin by Soviet and Polish troops and the subsequent German unconditional surrender on 8 May 1945. Following the Potsdam Declaration by the Allies on 26 July 1945, the United States dropped atomic bombs on the Japanese cities of Hiroshima and Nagasaki on 6 August and 9 August respectively. With an invasion of the Japanese archipelago imminent, the possibility of additional atomic bombings, and the Soviet Union's declaration of war on Japan and invasion of Manchuria, Japan surrendered on 15 August 1945. Thus ended the war in Asia, and the final destruction of the Axis bloc.

World War II altered the political alignment and social structure of the world. The United Nations (UN) was established to foster international co-operation and prevent future conflicts. The victorious great powers—the United States, the Soviet Union, China, the United Kingdom, and France—became the permanent members of the United Nations Security Council.[7] The Soviet Union and the United States emerged as rival superpowers, setting the stage for the Cold War, which lasted for the next 46 years. Meanwhile, the influence of European great powers waned, while the decolonisation of Asia and Africa began. Most countries whose industries had been damaged moved towards economic recovery. Political integration, especially in Europe, emerged as an effort to end pre-war enmities and to create a common identity.[8]
Contents

    1 Chronology
    2 Background
    3 Pre-war events
        3.1 Italian invasion of Ethiopia (1935)
        3.2 Spanish Civil War (1936–39)
        3.3 Japanese invasion of China (1937)
        3.4 Japanese invasion of the Soviet Union and Mongolia (1938)
        3.5 European occupations and agreements
    4 Course of the war
        4.1 War breaks out in Europe (1939–40)
        4.2 Western Europe (1940–41)
        4.3 Mediterranean (1940–41)
        4.4 Axis attack on the USSR (1941)
        4.5 War breaks out in the Pacific (1941)
        4.6 Axis advance stalls (1942–43)
        4.7 Allies gain momentum (1943–44)
        4.8 Allies close in (1944)
        4.9 Axis collapse, Allied victory (1944–45)
    5 Aftermath
    6 Impact
        6.1 Casualties and war crimes
        6.2 Concentration camps, slave labour, and genocide
        6.3 Occupation
        6.4 Home fronts and production
        6.5 Advances in technology and warfare
    7 See also
    8 Notes
    9 Citations
    10 References
    11 External links

Chronology
See also: Timeline of World War II

The start of the war in Europe is generally held to be 1 September 1939,[9][10] beginning with the German invasion of Poland; Britain and France declared war on Germany two days later. The dates for the beginning of war in the Pacific include the start of the Second Sino-Japanese War on 7 July 1937,[11] or even the Japanese invasion of Manchuria on 19 September 1931.[12][13]

Others follow the British historian A. J. P. Taylor, who held that the Sino-Japanese War and war in Europe and its colonies occurred simultaneously and the two wars merged in 1941. This article uses the conventional dating. Other starting dates sometimes used for World War II include the Italian invasion of Abyssinia on 3 October 1935.[14] The British historian Antony Beevor views the beginning of the Second World War as the Battles of Khalkhin Gol fought between Japan and the forces of Mongolia and the Soviet Union from May to September 1939.[15]

The exact date of the war's end is also not universally agreed upon. It was generally accepted at the time that the war ended with the armistice of 14 August 1945 (V-J Day), rather than the formal surrender of Japan (2 September 1945); it is even claimed in some European histories that it ended on V-E Day (8 May 1945).[citation needed] A peace treaty with Japan was signed in 1951 to formally tie up any loose ends such as compensation to be paid to Allied prisoners of war who had been victims of atrocities.[16] A treaty regarding Germany's future allowed the reunification of East and West Germany to take place in 1990 and resolved other post-World War II issues.[17]
Background
Main article: Causes of World War II

World War I had radically altered the political map, with the defeat of the Central Powers—including Austria-Hungary, Germany and the Ottoman Empire—and the 1917 Bolshevik seizure of power in Russia. Meanwhile, existing victorious Allies such as France, Belgium, Italy, Greece and Romania gained territories, whereas new states were created out of the collapse of Austria-Hungary and the Ottoman and Russian Empires.

To prevent the outbreak of a future world war, the League of Nations was formally created during the 1919 Paris Peace Conference. The organisation's primary goal was to prevent armed conflict through collective security, military and naval disarmament, and settling international disputes through peaceful negotiations and arbitration.

Despite strong pacifist sentiment after World War I,[18] its aftermath still caused irredentist and revanchist nationalism to become important in several European states. Irredentism and revanchism were strong in Germany because of the significant territorial, colonial, and financial losses incurred by the Treaty of Versailles. Under the treaty, Germany lost around 13 percent of its home territory and all of its overseas colonies, while German annexation of other states was prohibited, reparations were imposed, and limits were placed on the size and capability of the country's armed forces.[19] Meanwhile, the Russian Civil War had led to the creation of the Soviet Union.[20]

The German Empire was dissolved in the German Revolution of 1918–1919, and a democratic government, later known as the Weimar Republic, was created. The interwar period saw strife between supporters of the new republic and hardline opponents on both the right and left. Although Italy as an Entente ally made some territorial gains, Italian nationalists were angered that the promises made by Britain and France to secure Italian entrance into the war were not fulfilled with the peace settlement. From 1922 to 1925, the Fascist movement led by Benito Mussolini seized power in Italy with a nationalist, totalitarian, and class collaborationist agenda that abolished representative democracy, repressed socialist, left-wing and liberal forces, and pursued an aggressive foreign policy aimed at forcefully forging Italy as a world power, promising the creation of a "New Roman Empire".[21]
The League of Nations assembly, held in Geneva, Switzerland, 1930

In Germany, the Weimar Republic's legitimacy was challenged by right-wing elements such as the Freikorps and the Nazi party, resulting in events such as the Kapp Putsch and the Beer Hall Putsch. With the onset of the Great Depression in 1929, domestic support for Nazism and its leader Adolf Hitler rose and, in 1933, he was appointed Chancellor of Germany. In the aftermath of the Reichstag fire, Hitler created a totalitarian single-party state led by the Nazis.[22]

The Kuomintang (KMT) party in China launched a unification campaign against regional warlords and nominally unified China in the mid-1920s, but was soon embroiled in a civil war against its former Chinese communist allies.[23] In 1931, an increasingly militaristic Japanese Empire, which had long sought influence in China[24] as the first step of what its government saw as the country's right to rule Asia, used the Mukden Incident as a pretext to launch an invasion of Manchuria and establish the puppet state of Manchukuo.[25]

Too weak to resist Japan, China appealed to the League of Nations for help. Japan withdrew from the League of Nations after being condemned for its incursion into Manchuria. The two nations then fought several battles, in Shanghai, Rehe and Hebei, until the Tanggu Truce was signed in 1933. Thereafter, Chinese volunteer forces continued the resistance to Japanese aggression in Manchuria, and Chahar and Suiyuan.[26]
Adolf Hitler at a German National Socialist political rally in Weimar, October 1930

Adolf Hitler, after an unsuccessful attempt to overthrow the German government in 1923, eventually became the Chancellor of Germany in 1933. He abolished democracy, espousing a radical, racially motivated revision of the world order, and soon began a massive rearmament campaign.[27] It was at this time that multiple political scientists began to predict that a second Great War might take place.[28] Meanwhile, France, to secure its alliance, allowed Italy a free hand in Ethiopia, which Italy desired as a colonial possession. The situation was aggravated in early 1935 when the Territory of the Saar Basin was legally reunited with Germany and Hitler repudiated the Treaty of Versailles, accelerated his rearmament programme and introduced conscription.[29]

Hoping to contain Germany, the United Kingdom, France and Italy formed the Stresa Front; however, in June 1935, the United Kingdom made an independent naval agreement with Germany, easing prior restrictions. The Soviet Union, concerned due to Germany's goals of capturing vast areas of eastern Europe, wrote a treaty of mutual assistance with France. Before taking effect though, the Franco-Soviet pact was required to go through the bureaucracy of the League of Nations, which rendered it essentially toothless.[30] The United States, concerned with events in Europe and Asia, passed the Neutrality Act in August.[31] In October, Italy invaded Ethiopia through Italian Somaliland and Eritrea;[32] Germany was the only major European nation to support the invasion. Italy subsequently dropped its objections to Germany's goal of absorbing Austria.[33]

Hitler defied the Versailles and Locarno treaties by remilitarising the Rhineland in March 1936. He received little response from other European powers.[34] When the Spanish Civil War broke out in July, Hitler and Mussolini supported the fascist and authoritarian Nationalist forces in their civil war against the Soviet-supported Spanish Republic. Both sides used the conflict to test new weapons and methods of warfare,[35] with the Nationalists winning the war in early 1939. In October 1936, Germany and Italy formed the Rome–Berlin Axis. A month later, Germany and Japan signed the Anti-Comintern Pact, which Italy would join in the following year. In China, after the Xi'an Incident, the Kuomintang and communist forces agreed on a ceasefire to present a united front to oppose Japan.[36]
Pre-war events
Italian invasion of Ethiopia (1935)
Main article: Second Italo-Abyssinian War
Italian soldiers recruited in 1935, on their way to fight the Second Italo-Abyssinian War

The Second Italo–Abyssinian War was a brief colonial war that began in October 1935 and ended in May 1936. The war began with the invasion of the Ethiopian Empire (also known as Abyssinia) by the armed forces of the Kingdom of Italy (Regno d'Italia), which was launched from Italian Somaliland and Eritrea.[32] The war resulted in the military occupation of Ethiopia and its annexation into the newly created colony of Italian East Africa (Africa Orientale Italiana, or AOI); in addition, it exposed the weakness of the League of Nations as a force to preserve peace. Both Italy and Ethiopia were member nations, but the League did nothing when the former clearly violated the League's own Article X.[37]
Spanish Civil War (1936–39)
Main article: Spanish Civil War
The bombing of Guernica in 1937, sparked Europe-wide fears that the next war would be based on bombing of cities with very high civilian casualties

During the Spanish Civil War, Hitler and Mussolini lent military support to the Nationalist rebels, led by General Francisco Franco. The Soviet Union supported the existing government, the Spanish Republic. Over 30,000 foreign volunteers, known as the International Brigades, also fought against the Nationalists. Both Germany and the USSR used this proxy war as an opportunity to test in combat their most advanced weapons and tactics. The bombing of Guernica by the German Condor Legion in April 1937 heightened widespread concerns that the next major war would include extensive terror bombing attacks on civilians.[38][39] The Nationalists won the civil war in April 1939; Franco, now dictator, bargained with both sides during the Second World War, but never concluded any major agreements. He did send volunteers to fight on the eastern front under German command but Spain remained neutral and did not allow either side to use its territory.[40]
Japanese invasion of China (1937)
Main article: Second Sino-Japanese War
Japanese Imperial Army soldiers during the Battle of Shanghai, 1937

In July 1937, Japan captured the former Chinese imperial capital of Beijing after instigating the Marco Polo Bridge Incident, which culminated in the Japanese campaign to invade all of China.[41] The Soviets quickly signed a non-aggression pact with China to lend materiel support, effectively ending China's prior co-operation with Germany. Generalissimo Chiang Kai-shek deployed his best army to defend Shanghai, but, after three months of fighting, Shanghai fell. The Japanese continued to push the Chinese forces back, capturing the capital Nanking in December 1937. After the fall of Nanking, tens of thousands if not hundreds of thousands of Chinese civilians and disarmed combatants were murdered by the Japanese.[42][43]

In March 1938, Nationalist Chinese force got their first major victory at Taierzhuang but then city Xuzhou was taken by Japanese in May.[44] In June 1938, Chinese forces stalled the Japanese advance by flooding the Yellow River; this manoeuvre bought time for the Chinese to prepare their defences at Wuhan, but the city was taken by October.[45] Japanese military victories did not bring about the collapse of Chinese resistance that Japan had hoped to achieve; instead the Chinese government relocated inland to Chongqing and continued the war.[46][47]
Japanese invasion of the Soviet Union and Mongolia (1938)
See also: Nanshin-ron and Soviet–Japanese border conflicts

Japanese forces in Manchuoko had sporadic border clashes with the Soviet Union, culminating in the Japanese defeat at Khalkin Gol. After this, Japan and the Soviet Union signed a Neutrality Pact in April 1941, and Japan turned its focus to the South Pacific.
European occupations and agreements
Further information: Anschluss, Appeasement, Munich Agreement, German occupation of Czechoslovakia and Molotov–Ribbentrop Pact
Chamberlain, Daladier, Hitler, Mussolini, and Ciano pictured just before signing the Munich Agreement, 29 September 1938

In Europe, Germany and Italy were becoming more bold. In March 1938, Germany annexed Austria, again provoking little response from other European powers.[48] Encouraged, Hitler began pressing German claims on the Sudetenland, an area of Czechoslovakia with a predominantly ethnic German population; and soon Britain and France followed the counsel of prime minister Neville Chamberlain and conceded this territory to Germany in the Munich Agreement, which was made against the wishes of the Czechoslovak government, in exchange for a promise of no further territorial demands.[49] Soon afterwards, Germany and Italy forced Czechoslovakia to cede additional territory to Hungary and Poland.[50]

Although all of Germany's stated demands had been satisfied by the agreement, privately Hitler was furious that British interference had prevented him from seizing all of Czechoslovakia in one operation. In subsequent speeches Hitler attacked British and Jewish "war-mongers" and in January 1939 secretly ordered a major build-up of the German navy to challenge British naval supremacy. In March 1939, Germany invaded the remainder of Czechoslovakia and subsequently split it into the German Protectorate of Bohemia and Moravia and a pro-German client state, the Slovak Republic.[51] Hitler also delivered an ultimatum to Lithuania, forcing the concession of the Klaipėda Region.
German Foreign Minister Ribbentrop signing the Nazi–Soviet non-aggression pact. Standing behind him are Molotov and the Soviet leader Joseph Stalin, 1939

Alarmed, and with Hitler making further demands on the Free City of Danzig, France and Britain guaranteed their support for Polish independence; when Italy conquered Albania in April 1939, the same guarantee was extended to Romania and Greece.[52] Shortly after the Franco-British pledge to Poland, Germany and Italy formalised their own alliance with the Pact of Steel.[53] Hitler accused Britain and Poland of trying to "encircle" Germany and renounced the Anglo-German Naval Agreement and the German–Polish Non-Aggression Pact.

In August 1939, Germany and the Soviet Union signed the Molotov–Ribbentrop Pact,[54] a non-aggression treaty with a secret protocol. The parties gave each other rights to "spheres of influence" (western Poland and Lithuania for Germany; eastern Poland, Finland, Estonia, Latvia and Bessarabia for the USSR). It also raised the question of continuing Polish independence.[55] The agreement was crucial to Hitler because it assured that Germany would not have to face the prospect of a two-front war, as it had in World War I, after it defeated Poland.

The situation reached a general crisis in late August as German troops continued to mobilise against the Polish border. In a private meeting with the Italian foreign minister, Count Ciano, Hitler asserted that Poland was a "doubtful neutral" that needed to either yield to his demands or be "liquidated" to prevent it from drawing off German troops in the future "unavoidable" war with the Western democracies. He did not believe Britain or France would intervene in the conflict.[56] On 23 August Hitler ordered the attack to proceed on 26 August, but upon hearing that Britain had concluded a formal mutual assistance pact with Poland and that Italy would maintain neutrality, he decided to delay it.[57] In response to British pleas for direct negotiations, Germany demanded on 29 August that a Polish plenipotentiary immediately travel to Berlin to negotiate the handover of Danzig and the Polish Corridor to Germany as well as to agree to safeguard the German minority in Poland. The Poles refused to comply with this request and on the evening of 31 August Germany declared that it considered its proposals rejected.[58]
Course of the war
Further information: Diplomatic history of World War II
War breaks out in Europe (1939–40)
Main articles: Invasion of Poland, Occupation of Poland (1939–45), Nazi crimes against the Polish nation, Soviet invasion of Poland and Soviet repressions of Polish citizens (1939–46)
Soldiers of the German Wehrmacht tearing down the border crossing between Poland and the Free City of Danzig, 1 September 1939

On 1 September 1939, Germany invaded Poland under the false pretext that the Poles had carried out a series of sabotage operations against German targets.[59] Two days later, on 3 September, France and United Kingdom, followed by the fully independent Dominions[60] of the British Commonwealth[61]—Australia (3 September), Canada (10 September), New Zealand (3 September), and South Africa (6 September)—declared war on Germany. However, initially the alliance provided limited direct military support to Poland, consisting of a small French attack into the Saarland.[62] The Western Allies also began a naval blockade of Germany, which aimed to damage the country's economy and war effort.[63] Germany responded by ordering U-boat warfare against Allied merchant and war ships, which was to later escalate in the Battle of the Atlantic.
German Panzer I tanks near the city of Bydgoszcz, during the Invasion of Poland, September 1939

On 17 September 1939, after signing a cease-fire with Japan, the Soviets also invaded Poland from the east.[64] The Polish army was defeated and Warsaw surrendered to the Germans on 27 September, with final pockets of resistance surrendering on 6 October. Poland's territory was divided between Germany and the Soviet Union, with Lithuania and Slovakia also receiving small shares. After the surrender of Poland's armed forces, Polish resistance established an Underground State, a partisan Home Army, and continued to fight alongside the Allies on all fronts in Europe and North Africa, throughout the entire course of the war.[65]

About 100,000 Polish military personnel were evacuated to Romania and the Baltic countries; many of these soldiers later fought against the Germans in other theatres of the war.[66] Poland's Enigma codebreakers were also evacuated to France.[67]

On 6 October Hitler made a public peace overture to the United Kingdom and France, but said that the future of Poland was to be determined exclusively by Germany and the Soviet Union. Chamberlain rejected this on 12 October, saying "Past experience has shown that no reliance can be placed upon the promises of the present German Government."[58] After this rejection Hitler ordered an immediate offensive against France,[68] but bad weather forced repeated postponements until the spring of 1940.[69][70][71]

After signing the German-Soviet treaty governing Lithuania, the Soviet Union forced the Baltic countries to allow it to station Soviet troops in their countries under pacts of "mutual assistance."[72][73][74] Finland rejected territorial demands, prompting a Soviet invasion in November 1939.[75] The resulting Winter War ended in March 1940 with Finnish concessions.[76] The United Kingdom and France treating the Soviet attack on Finland as tantamount to its entering the war on the side of the Germans, responded to the Soviet invasion by supporting the USSR's expulsion from the League of Nations.[74]
Western Europe (1940–41)
Map of the French Maginot Line

In April 1940, Germany invaded Denmark and Norway to protect shipments of iron ore from Sweden, which the Allies were attempting to cut off by unilaterally mining neutral Norwegian waters.[77] Denmark capitulated after a few hours, and despite Allied support, during which the important harbour of Narvik temporarily was recaptured by the British, Norway was conquered within two months.[78] British discontent over the Norwegian campaign led to the replacement of the British Prime Minister, Neville Chamberlain, with Winston Churchill on 10 May 1940.[79]

Germany launched an offensive against France and, for reasons of military strategy, also attacked the neutral nations of Belgium, the Netherlands, and Luxembourg on 10 May 1940.[80] That same day the United Kingdom occupied the Danish possessions of Iceland, Greenland and the Faroes to preempt a possible German invasion of the islands.[81] The Netherlands and Belgium were overrun using blitzkrieg tactics in a few days and weeks, respectively.[82] The French-fortified Maginot Line and the main body the Allied forces which had moved into Belgium were circumvented by a flanking movement through the thickly wooded Ardennes region,[83] mistakenly perceived by Allied planners as an impenetrable natural barrier against armoured vehicles.[84] As a result, the bulk of the Allied armies found themselves trapped in an encirclement and were beaten. The majority were taken prisoner, whilst over 300,000, mostly British and French, were evacuated from the continent at Dunkirk by early June, although abandoning almost all of their equipment.[85]

On 10 June, Italy invaded France, declaring war on both France and the United Kingdom.[86] Paris fell to the Germans on 14 June and eight days later France surrendered and was soon divided into German and Italian occupation zones,[87] and an unoccupied rump state under the Vichy Regime, which, though officially neutral, was generally aligned with Germany. France kept its fleet but the British feared the Germans would seize it, so on 3 July, the British attacked it.[88]

In June 1940, the Soviet Union forcibly annexed Estonia, Latvia and Lithuania,[73] and then annexed the disputed Romanian region of Bessarabia. Meanwhile, Nazi-Soviet political rapprochement and economic co-operation[89][90] gradually stalled,[91][92] and both states began preparations for war.[93]
View of London after the German "Blitz", 29 December 1940

On 19 July, Hitler again publicly offered to end the war, saying he had no desire to destroy the British Empire. The United Kingdom rejected this, with Lord Halifax responding "there was in his speech no suggestion that peace must be based on justice, no word of recognition that the other nations of Europe had any right to self‑determination ..."[94]

Following this, Germany began an air superiority campaign over the United Kingdom (the Battle of Britain) to prepare for an invasion.[95] The campaign failed, and the invasion plans were cancelled by September.[95] Frustrated, and in part in response to repeated British air raids against Berlin, Germany began a strategic bombing offensive against British cities known as the Blitz.[96] However, the air attacks largely failed to disrupt the British war effort.
German Luftwaffe, Heinkel He 111 bombers during the Battle of Britain

Using newly captured French ports, the German Navy enjoyed success against an over-extended Royal Navy, using U-boats against British shipping in the Atlantic.[97] The British scored a significant victory on 27 May 1941 by sinking the German battleship Bismarck.[98] Perhaps most importantly, during the Battle of Britain the Royal Air Force had successfully resisted the Luftwaffe's assault, and the German bombing campaign largely ended in May 1941.[99]

Throughout this period, the neutral United States took measures to assist China and the Western Allies. In November 1939, the American Neutrality Act was amended to allow "cash and carry" purchases by the Allies.[100] In 1940, following the German capture of Paris, the size of the United States Navy was significantly increased. In September, the United States further agreed to a trade of American destroyers for British bases.[101] Still, a large majority of the American public continued to oppose any direct military intervention into the conflict well into 1941.[102]

Although Roosevelt had promised to keep the United States out of the war, he nevertheless took concrete steps to prepare for that eventuality. In December 1940 he accused Hitler of planning world conquest and ruled out negotiations as useless, calling for the US to become an "arsenal for democracy" and promoted the passage of Lend-Lease aid to support the British war effort.[94] In January 1941 secret high level staff talks with the British began for the purposes of determining how to defeat Germany should the US enter the war. They decided on a number of offensive policies, including an air offensive, the "early elimination" of Italy, raids, support of resistance groups, and the capture of positions to launch an offensive against Germany.[103]

At the end of September 1940, the Tripartite Pact united Japan, Italy and Germany to formalise the Axis Powers. The Tripartite Pact stipulated that any country, with the exception of the Soviet Union, not in the war which attacked any Axis Power would be forced to go to war against all three.[104] The Axis expanded in November 1940 when Hungary, Slovakia and Romania joined the Tripartite Pact.[105] Romania would make a major contribution (as did Hungary) to the Axis war against the USSR, partially to recapture territory ceded to the USSR, partially to pursue its leader Ion Antonescu's desire to combat communism.[106]
Mediterranean (1940–41)
Australian troops of the British Commonwealth Forces man a front-line trench during the Siege of Tobruk; North African Campaign, August 1941

Italy began operations in the Mediterranean, initiating a siege of Malta in June, conquering British Somaliland in August, and making an incursion into British-held Egypt in September 1940. In October 1940, Italy started the Greco-Italian War due to Mussolini's jealousy of Hitler's success but within days was repulsed and pushed back into Albania, where a stalemate soon occurred.[107] The United Kingdom responded to Greek requests for assistance by sending troops to Crete and providing air support to Greece. Hitler decided that when the weather improved he would take action against Greece to assist the Italians and prevent the British from gaining a foothold in the Balkans, to strike against the British naval dominance of the Mediterranean, and to secure his hold on Romanian oil.[108]

In December 1940, British Commonwealth forces began counter-offensives against Italian forces in Egypt and Italian East Africa.[109] The offensive in North Africa was highly successful and by early February 1941 Italy had lost control of eastern Libya and large numbers of Italian troops had been taken prisoner. The Italian Navy also suffered significant defeats, with the Royal Navy putting three Italian battleships out of commission by a carrier attack at Taranto, and neutralising several more warships at the Battle of Cape Matapan.[110]

The Germans soon intervened to assist Italy. Hitler sent German forces to Libya in February, and by the end of March they had launched an offensive which drove back the Commonwealth forces which had been weakened to support Greece.[111] In under a month, Commonwealth forces were pushed back into Egypt with the exception of the besieged port of Tobruk.[112] The Commonwealth attempted to dislodge Axis forces in May and again in June, but failed on both occasions.[113]

By late March 1941, following Bulgaria's signing of the Tripartite Pact, the Germans were in position to intervene in Greece. Plans were changed, however, due to developments in neighbouring Yugoslavia. The Yugoslav government had signed the Tripartite Pact on 25 March, only to be overthrown two days later by a British-encouraged coup. Hitler viewed the new regime as hostile and immediately decided to eliminate it. On 6 April Germany simultaneously invaded both Yugoslavia and Greece, making rapid progress and forcing both nations to surrender within the month. The British were driven from the Balkans after Germany conquered the Greek island of Crete by the end of May.[114] Although the Axis victory was swift, bitter partisan warfare subsequently broke out against the Axis occupation of Yugoslavia, which continued until the end of the war.

The Allies did have some successes during this time. In the Middle East, Commonwealth forces first quashed an uprising in Iraq which had been supported by German aircraft from bases within Vichy-controlled Syria,[115] then, with the assistance of the Free French, invaded Syria and Lebanon to prevent further such occurrences.[116]
Axis attack on the USSR (1941)
Further information: Operation Barbarossa, Einsatzgruppen, World War II casualties of the Soviet Union and Nazi crimes against Soviet POWs
Animation of the WWII European Theatre
Soviet civilians in Leningrad leaving destroyed houses, after a German bombardment of the city; Battle of Leningrad, 10 December 1942

With the situation in Europe and Asia relatively stable, Germany, Japan, and the Soviet Union made preparations. With the Soviets wary of mounting tensions with Germany and the Japanese planning to take advantage of the European War by seizing resource-rich European possessions in Southeast Asia, the two powers signed the Soviet–Japanese Neutrality Pact in April 1941.[117] By contrast, the Germans were steadily making preparations for an attack on the Soviet Union, massing forces on the Soviet border.[118]

Hitler believed that Britain's refusal to end the war was based on the hope that the United States and the Soviet Union would enter the war against Germany sooner or later.[119] He therefore decided to try to strengthen Germany's relations with the Soviets, or failing that, to attack and eliminate them as a factor. In November 1940 negotiations took place to determine if the Soviet Union would join the Tripartite Pact. The Soviets showed some interest, but asked for concessions from Finland, Bulgaria, Turkey, and Japan that Germany considered unacceptable. On 18 December 1940 Hitler issued the directive to prepare for an invasion of the Soviet Union.

On 22 June 1941, Germany, supported by Italy and Romania, invaded the Soviet Union in Operation Barbarossa, with Germany accusing the Soviets of plotting against them. They were joined shortly by Finland and Hungary.[120] The primary targets of this surprise offensive[121] were the Baltic region, Moscow and Ukraine, with the ultimate goal of ending the 1941 campaign near the Arkhangelsk-Astrakhan line, from the Caspian to the White Seas. Hitler's objectives were to eliminate the Soviet Union as a military power, exterminate Communism, generate Lebensraum ("living space")[122] by dispossessing the native population[123] and guarantee access to the strategic resources needed to defeat Germany's remaining rivals.[124]

Although the Red Army was preparing for strategic counter-offensives before the war,[125] Barbarossa forced the Soviet supreme command to adopt a strategic defence. During the summer, the Axis made significant gains into Soviet territory, inflicting immense losses in both personnel and materiel. By the middle of August, however, the German Army High Command decided to suspend the offensive of a considerably depleted Army Group Centre, and to divert the 2nd Panzer Group to reinforce troops advancing towards central Ukraine and Leningrad.[126] The Kiev offensive was overwhelmingly successful, resulting in encirclement and elimination of four Soviet armies, and made further advance into Crimea and industrially developed Eastern Ukraine (the First Battle of Kharkov) possible.[127]

The diversion of three quarters of the Axis troops and the majority of their air forces from France and the central Mediterranean to the Eastern Front[128] prompted Britain to reconsider its grand strategy.[129] In July, the UK and the Soviet Union formed a military alliance against Germany[130] The British and Soviets invaded Iran to secure the Persian Corridor and Iran's oil fields.[131] In August, the United Kingdom and the United States jointly issued the Atlantic Charter.[132]

By October Axis operational objectives in Ukraine and the Baltic region were achieved, with only the sieges of Leningrad[133] and Sevastopol continuing.[134] A major offensive against Moscow was renewed; after two months of fierce battles in increasingly harsh weather the German army almost reached the outer suburbs of Moscow, where the exhausted troops[135] were forced to suspend their offensive.[136] Large territorial gains were made by Axis forces, but their campaign had failed to achieve its main objectives: two key cities remained in Soviet hands, the Soviet capability to resist was not broken, and the Soviet Union retained a considerable part of its military potential. The blitzkrieg phase of the war in Europe had ended.[137]

By early December, freshly mobilised reserves[138] allowed the Soviets to achieve numerical parity with Axis troops.[139] This, as well as intelligence data which established that a minimal number of Soviet troops in the East would be sufficient to deter any attack by the Japanese Kwantung Army,[140] allowed the Soviets to begin a massive counter-offensive that started on 5 December all along the front and pushed German troops 100–250 kilometres (62–155 mi) west.[141]
War breaks out in the Pacific (1941)
Mitsubishi A6M2, "Zero" fighters on the Imperial Japanese Navy aircraft carrier Shōkaku, just before the attack on Pearl Harbor

In 1939 the United States had renounced its trade treaty with Japan and beginning with an aviation gasoline ban in July 1940 Japan had become subject to increasing economic pressure.[94] During this time, Japan launched its first attack against Changsha, a strategically important Chinese city, but was repulsed by late September.[142] Despite several offensives by both sides, the war between China and Japan was stalemated by 1940. To increase pressure on China by blocking supply routes, and to better position Japanese forces in the event of a war with the Western powers, Japan had occupied northern Indochina.[143] Afterwards, the United States embargoed iron, steel and mechanical parts against Japan.[144] Other sanctions soon followed.

In August of that year, Chinese communists launched an offensive in Central China; in retaliation, Japan instituted harsh measures in occupied areas to reduce human and material resources for the communists.[145] Continued antipathy between Chinese communist and nationalist forces culminated in armed clashes in January 1941, effectively ending their co-operation.[146] In March, the Japanese 11th army attacked the headquarters of the Chinese 19th army but was repulsed during Battle of Shanggao.[147] In September, Japan attempted to take the city of Changsha again and clashed with Chinese nationalist forces.[148]

German successes in Europe encouraged Japan to increase pressure on European governments in Southeast Asia. The Dutch government agreed to provide Japan some oil supplies from the Dutch East Indies, but negotiations for additional access to their resources ended in failure in June 1941.[149] In July 1941 Japan sent troops to southern Indochina, thus threatening British and Dutch possessions in the Far East. The United States, United Kingdom and other Western governments reacted to this move with a freeze on Japanese assets and a total oil embargo.[150][151]

Since early 1941 the United States and Japan had been engaged in negotiations in an attempt to improve their strained relations and end the war in China. During these negotiations Japan advanced a number of proposals which were dismissed by the Americans as inadequate.[152] At the same time the US, Britain, and the Netherlands engaged in secret discussions for the joint defence of their territories, in the event of a Japanese attack against any of them.[153] Roosevelt reinforced the Philippines (an American possession since 1898) and warned Japan that the US would react to Japanese attacks against any "neighboring countries".[153]
USS Arizona during the Japanese surprise air attack on the American pacific fleet, 7 December 1941

Frustrated at the lack of progress and feeling the pinch of the American-British-Dutch sanctions, Japan prepared for war. On 20 November it presented an interim proposal as its final offer. It called for the end of American aid to China and the supply of oil and other resources to Japan. In exchange they promised not to launch any attacks in Southeast Asia and to withdraw their forces from their threatening positions in southern Indochina.[152] The American counter-proposal of 26 November required that Japan evacuate all of China without conditions and conclude non-aggression pacts with all Pacific powers.[154] That meant Japan was essentially forced to choose between abandoning its ambitions in China, or seizing the natural resources it needed in the Dutch East Indies by force;[155] the Japanese military did not consider the former an option, and many officers considered the oil embargo an unspoken declaration of war.[156]

Japan planned to rapidly seize European colonies in Asia to create a large defensive perimeter stretching into the Central Pacific; the Japanese would then be free to exploit the resources of Southeast Asia while exhausting the over-stretched Allies by fighting a defensive war.[157] To prevent American intervention while securing the perimeter it was further planned to neutralise the United States Pacific Fleet and the American military presence in the Philippines from the outset.[158] On 7 December (8 December in Asian time zones), 1941, Japan attacked British and American holdings with near-simultaneous offensives against Southeast Asia and the Central Pacific.[159] These included an attack on the American fleet at Pearl Harbor, landings in Thailand and Malaya[159] and the battle of Hong Kong.

These attacks led the United States, Britain, China, Australia and several other states to formally declare war on Japan, whereas the Soviet Union, being heavily involved in large-scale hostilities with European Axis countries, preferred to maintain its neutrality agreement with Japan.[160] Germany, followed by the other Axis states, declared war on the United States in solidarity with Japan, citing as justification the American attacks on German submarines and merchant ships that had been ordered by Roosevelt.[120]
Axis advance stalls (1942–43)
Seated at the Casablanca Conference; US President Franklin D. Roosevelt and British PM Winston Churchill, January 1943

In January 1942, the United States, Britain, Soviet Union, China, and 22 smaller or exiled governments issued the Declaration by United Nations, thereby affirming the Atlantic Charter,[161] and agreeing to not to sign separate peace with the Axis powers.

During 1942 Allied officials debated on the appropriate grand strategy to pursue. All agreed that defeating Germany was the primary objective. The Americans favoured a straightforward, large-scale attack on Germany through France. The Soviets were also demanding a second front. The British, on the other hand, argued that military operations should target peripheral areas to throw a "ring" around Germany which would wear out German strength, lead to increasing demoralisation, and bolster resistance forces. Germany itself would be subject to a heavy bombing campaign. An offensive against Germany would then be launched primarily by Allied armour without using large-scale armies.[162] Eventually, the British persuaded the Americans that a landing in France was infeasible in 1942 and they should instead focus on driving the Axis out of North Africa.[163]

At the Casablanca Conference in early 1943 the Allies issued a declaration declaring that they would not negotiate with their enemies and demanded their unconditional surrender. The British and Americans agreed to continue to press the initiative in the Mediterranean by invading Sicily to fully secure the Mediterranean supply routes.[164] Although the British argued for further operations in the Balkans to bring Turkey into the war, in May 1943 the Americans extracted a British commitment to limit Allied operations in the Mediterranean to an invasion of the Italian mainland and to invade France in 1944.[165]
Pacific (1942–43)
Map of Japanese military advances, until mid-1942

By the end of April 1942, Japan and its ally Thailand had almost fully conquered Burma, Malaya, the Dutch East Indies, Singapore, and Rabaul, inflicting severe losses on Allied troops and taking a large number of prisoners.[166] Despite stubborn resistance at Corregidor, the US possession of the Philippines was eventually captured in May 1942, forcing its government into exile.[167] On 16 April, in Burma 7,000 British soldiers were encircled by the Japanese 33rd Division during the Battle of Yenangyaung and rescued by the Chinese 38th Division.[168] Japanese forces also achieved naval victories in the South China Sea, Java Sea and Indian Ocean,[169] and bombed the Allied naval base at Darwin, Australia. The only real Allied success against Japan was a Chinese victory at Changsha in early January 1942.[170] These easy victories over unprepared opponents left Japan overconfident, as well as overextended.[171]

In early May 1942, Japan initiated operations to capture Port Moresby by amphibious assault and thus sever communications and supply lines between the United States and Australia. The Allies, however, prevented the invasion by intercepting and defeating the Japanese naval forces in the Battle of the Coral Sea.[172] Japan's next plan, motivated by the earlier Doolittle Raid, was to seize Midway Atoll and lure American carriers into battle to be eliminated; as a diversion, Japan would also send forces to occupy the Aleutian Islands in Alaska.[173] In early June, Japan put its operations into action but the Americans, having broken Japanese naval codes in late May, were fully aware of the plans and force dispositions and used this knowledge to achieve a decisive victory at Midway over the Imperial Japanese Navy.[174]
US Marines during the Guadalcanal Campaign, in the Pacific theatre, 1942

With its capacity for aggressive action greatly diminished as a result of the Midway battle, Japan chose to focus on a belated attempt to capture Port Moresby by an overland campaign in the Territory of Papua.[175] The Americans planned a counter-attack against Japanese positions in the southern Solomon Islands, primarily Guadalcanal, as a first step towards capturing Rabaul, the main Japanese base in Southeast Asia.[176]

Both plans started in July, but by mid-September, the Battle for Guadalcanal took priority for the Japanese, and troops in New Guinea were ordered to withdraw from the Port Moresby area to the northern part of the island, where they faced Australian and United States troops in the Battle of Buna-Gona.[177] Guadalcanal soon became a focal point for both sides with heavy commitments of troops and ships in the battle for Guadalcanal. By the start of 1943, the Japanese were defeated on the island and withdrew their troops.[178] In Burma, Commonwealth forces mounted two operations. The first, an offensive into the Arakan region in late 1942, went disastrously, forcing a retreat back to India by May 1943.[179] The second was the insertion of irregular forces behind Japanese front-lines in February which, by the end of April, had achieved mixed results.[180]
Eastern Front (1942–43)
Red Army soldiers on the counterattack, during the Battle of Stalingrad, February 1943

Despite considerable losses, in early 1942 Germany and its allies stopped a major Soviet offensive in Central and Southern Russia, keeping most territorial gains they had achieved during the previous year.[181] In May the Germans defeated Soviet offensives in the Kerch Peninsula and at Kharkiv,[182] and then launched their main summer offensive against southern Russia in June 1942, to seize the oil fields of the Caucasus and occupy Kuban steppe, while maintaining positions on the northern and central areas of the front. The Germans split Army Group South into two groups: Army Group A struck lower Don River while Army Group B struck south-east to the Caucasus, towards Volga River.[183] The Soviets decided to make their stand at Stalingrad, which was in the path of the advancing German armies.

By mid-November, the Germans had nearly taken Stalingrad in bitter street fighting when the Soviets began their second winter counter-offensive, starting with an encirclement of German forces at Stalingrad[184] and an assault on the Rzhev salient near Moscow, though the latter failed disastrously.[185] By early February 1943, the German Army had taken tremendous losses; German troops at Stalingrad had been forced to surrender,[186] and the front-line had been pushed back beyond its position before the summer offensive. In mid-February, after the Soviet push had tapered off, the Germans launched another attack on Kharkiv, creating a salient in their front line around the Russian city of Kursk.[187]
Western Europe/Atlantic & Mediterranean (1942–43)
An American B-17 bombing raid, by the 8th Air Force, on the Focke Wulf factory in Germany, 9 October 1943

Exploiting poor American naval command decisions, the German navy ravaged Allied shipping off the American Atlantic coast.[188] By November 1941, Commonwealth forces had launched a counter-offensive, Operation Crusader, in North Africa, and reclaimed all the gains the Germans and Italians had made.[189] In North Africa, the Germans launched an offensive in January, pushing the British back to positions at the Gazala Line by early February,[190] followed by a temporary lull in combat which Germany used to prepare for their upcoming offensives.[191] Concerns the Japanese might use bases in Vichy-held Madagascar caused the British to invade the island in early May 1942.[192] An Axis offensive in Libya forced an Allied retreat deep inside Egypt until Axis forces were stopped at El Alamein.[193] On the Continent, raids of Allied commandos on strategic targets, culminating in the disastrous Dieppe Raid,[194] demonstrated the Western Allies' inability to launch an invasion of continental Europe without much better preparation, equipment, and operational security.[195]

In August 1942, the Allies succeeded in repelling a second attack against El Alamein[196] and, at a high cost, managed to deliver desperately needed supplies to the besieged Malta.[197] A few months later, the Allies commenced an attack of their own in Egypt, dislodging the Axis forces and beginning a drive west across Libya.[198] This attack was followed up shortly after by Anglo-American landings in French North Africa, which resulted in the region joining the Allies.[199] Hitler responded to the French colony's defection by ordering the occupation of Vichy France;[199] although Vichy forces did not resist this violation of the armistice, they managed to scuttle their fleet to prevent its capture by German forces.[200] The now pincered Axis forces in Africa withdrew into Tunisia, which was conquered by the Allies in May 1943.[201]

In early 1943 the British and Americans began the "Combined Bomber Offensive", a strategic bombing campaign against Germany. The goals were to disrupt the German war economy, reduce German morale, and "de-house" the German civilian population.[202]
Allies gain momentum (1943–44)
US Navy Douglas SBD Dauntless flies patrol over the USS Washington and USS Lexington during the Gilbert and Marshall Islands campaign, 1943

Following the Guadalcanal Campaign, the Allies initiated several operations against Japan in the Pacific. In May 1943, Allied forces were sent to eliminate Japanese forces from the Aleutians,[203] and soon after began major operations to isolate Rabaul by capturing surrounding islands, and to breach the Japanese Central Pacific perimeter at the Gilbert and Marshall Islands.[204] By the end of March 1944, the Allies had completed both of these objectives, and additionally neutralised the major Japanese base at Truk in the Caroline Islands. In April, the Allies then launched an operation to retake Western New Guinea.[205]

In the Soviet Union, both the Germans and the Soviets spent the spring and early summer of 1943 making preparations for large offensives in Central Russia. On 4 July 1943, Germany attacked Soviet forces around the Kursk Bulge. Within a week, German forces had exhausted themselves against the Soviets' deeply echeloned and well-constructed defences[206] and, for the first time in the war, Hitler cancelled the operation before it had achieved tactical or operational success.[207] This decision was partially affected by the Western Allies' invasion of Sicily launched on 9 July which, combined with previous Italian failures, resulted in the ousting and arrest of Mussolini later that month.[208] Also, in July 1943 the British firebombed Hamburg killing over 40,000 people.
Red Army troops following T-34 tanks, in a counter-offensive on German positions, at the Battle of Kursk, August 1943

On 12 July 1943, the Soviets launched their own counter-offensives, thereby dispelling any hopes of the German Army for victory or even stalemate in the east. The Soviet victory at Kursk marked the end of German superiority,[209] giving the Soviet Union the initiative on the Eastern Front.[210][211] The Germans attempted to stabilise their eastern front along the hastily fortified Panther-Wotan line, however, the Soviets broke through it at Smolensk and by the Lower Dnieper Offensives.[212]

On 3 September 1943, the Western Allies invaded the Italian mainland, following an Italian armistice with the Allies.[213] Germany responded by disarming Italian forces, seizing military control of Italian areas,[214] and creating a series of defensive lines.[215] German special forces then rescued Mussolini, who then soon established a new client state in German occupied Italy named the Italian Social Republic,[216] causing an Italian civil war. The Western Allies fought through several lines until reaching the main German defensive line in mid-November.[217]

German operations in the Atlantic also suffered. By May 1943, as Allied counter-measures became increasingly effective, the resulting sizeable German submarine losses forced a temporary halt of the German Atlantic naval campaign.[218] In November 1943, Franklin D. Roosevelt and Winston Churchill met with Chiang Kai-shek in Cairo and then with Joseph Stalin in Tehran.[219] The former conference determined the post-war return of Japanese territory,[220] while the latter included agreement that the Western Allies would invade Europe in 1944 and that the Soviet Union would declare war on Japan within three months of Germany's defeat.[221]
Ruins of the Benedictine monastery, during the Battle of Monte Cassino; Italian Campaign, May 1944

From November 1943, during the seven-week Battle of Changde, the Chinese forced Japan to fight a costly war of attrition, while awaiting Allied relief.[222][223][224] In January 1944, the Allies launched a series of attacks in Italy against the line at Monte Cassino and attempted to outflank it with landings at Anzio.[225] By the end of January, a major Soviet offensive expelled German forces from the Leningrad region,[226] ending the longest and most lethal siege in history.

The following Soviet offensive was halted on the pre-war Estonian border by the German Army Group North aided by Estonians hoping to re-establish national independence. This delay slowed subsequent Soviet operations in the Baltic Sea region.[227] By late May 1944, the Soviets had liberated Crimea, largely expelled Axis forces from Ukraine, and made incursions into Romania, which were repulsed by the Axis troops.[228] The Allied offensives in Italy had succeeded and, at the expense of allowing several German divisions to retreat, on 4 June, Rome was captured.[229]

The Allies experienced mixed fortunes in mainland Asia. In March 1944, the Japanese launched the first of two invasions, an operation against British positions in Assam, India,[230] and soon besieged Commonwealth positions at Imphal and Kohima.[231] In May 1944, British forces mounted a counter-offensive that drove Japanese troops back to Burma,[231] and Chinese forces that had invaded northern Burma in late 1943 besieged Japanese troops in Myitkyina.[232] The second Japanese invasion of China attempted to destroy China's main fighting forces, secure railways between Japanese-held territory and capture Allied airfields.[233] By June, the Japanese had conquered the province of Henan and begun a renewed attack against Changsha in the Hunan province.[234]
Allies close in (1944)
American troops approaching Omaha Beach, during the Invasion of Normandy on D-Day, 6 June 1944

On 6 June 1944 (known as D-Day), after three years of Soviet pressure,[235] the Western Allies invaded northern France. After reassigning several Allied divisions from Italy, they also attacked southern France.[236] These landings were successful, and led to the defeat of the German Army units in France. Paris was liberated by the local resistance assisted by the Free French Forces on 25 August[237] and the Western Allies continued to push back German forces in Western Europe during the latter part of the year. An attempt to advance into northern Germany spearheaded by a major airborne operation in the Netherlands ended with a failure.[238] After that, the Western Allies slowly pushed into Germany, unsuccessfully trying to cross the Rur river in a large offensive. In Italy the Allied advance also slowed down, when they ran into the last major German defensive line.[239]

On 22 June, the Soviets launched a strategic offensive in Belarus (known as "Operation Bagration") that resulted in the almost complete destruction of the German Army Group Centre.[240] Soon after that, another Soviet strategic offensive forced German troops from Western Ukraine and Eastern Poland. The successful advance of Soviet troops prompted resistance forces in Poland to initiate several uprisings. Though, the largest of these in Warsaw, where German soldiers massacred 200,000 civilians, as well as a national Slovak Uprising in the south did not receive Soviet support, and were put down by German forces.[241] The Red Army's strategic offensive in eastern Romania cut off and destroyed the considerable German troops there and triggered a successful coup d'état in Romania and in Bulgaria, followed by those countries' shift to the Allied side.[242]
German SS soldiers from the Dirlewanger Brigade, tasked with suppressing partisan uprisings against Nazi occupation, August 1944

In September 1944, Soviet Red Army troops advanced into Yugoslavia and forced the rapid withdrawal of the German Army Groups E and F in Greece, Albania and Yugoslavia to rescue them from being cut off.[243] By this point, the Communist-led Partisans under Marshal Josip Broz Tito, who had led an increasingly successful guerrilla campaign against the occupation since 1941, controlled much of the territory of Yugoslavia and were engaged in delaying efforts against the German forces further south. In northern Serbia, the Red Army, with limited support from Bulgarian forces, assisted the Partisans in a joint liberation of the capital city of Belgrade on 20 October. A few days later, the Soviets launched a massive assault against German-occupied Hungary that lasted until the fall of Budapest in February 1945.[244] In contrast with impressive Soviet victories in the Balkans, the bitter Finnish resistance to the Soviet offensive in the Karelian Isthmus denied the Soviets occupation of Finland and led to the signing of Soviet-Finnish armistice on relatively mild conditions,[245][246] with a subsequent shift to the Allied side by Finland.

By the start of July, Commonwealth forces in Southeast Asia had repelled the Japanese sieges in Assam, pushing the Japanese back to the Chindwin River[247] while the Chinese captured Myitkyina. In China, the Japanese were having greater successes, having finally captured Changsha in mid-June and the city of Hengyang by early August.[248] Soon after, they further invaded the province of Guangxi, winning major engagements against Chinese forces at Guilin and Liuzhou by the end of November[249] and successfully linking up their forces in China and Indochina by the middle of December.[250]

In the Pacific, American forces continued to press back the Japanese perimeter. In mid-June 1944 they began their offensive against the Mariana and Palau islands, and decisively defeated Japanese forces in the Battle of the Philippine Sea. These defeats led to the resignation of the Japanese Prime Minister, Hideki Tojo, and provided the United States with air bases to launch intensive heavy bomber attacks on the Japanese home islands. In late October, American forces invaded the Filipino island of Leyte; soon after, Allied naval forces scored another large victory during the Battle of Leyte Gulf, one of the largest naval battles in history.[251]
Axis collapse, Allied victory (1944–45)
Yalta Conference held in February 1945, with Winston Churchill, Franklin D. Roosevelt and Joseph Stalin

On 16 December 1944, Germany attempted its last desperate measure for success on the Western Front by using most of its remaining reserves to launch a massive counter-offensive in the Ardennes to attempt to split the Western Allies, encircle large portions of Western Allied troops and capture their primary supply port at Antwerp to prompt a political settlement.[252] By January, the offensive had been repulsed with no strategic objectives fulfilled.[252] In Italy, the Western Allies remained stalemated at the German defensive line. In mid-January 1945, the Soviets and Poles attacked in Poland, pushing from the Vistula to the Oder river in Germany, and overran East Prussia.[253] On 4 February, US, British, and Soviet leaders met for the Yalta Conference. They agreed on the occupation of post-war Germany, and on when the Soviet Union would join the war against Japan.[254]

In February, the Soviets invaded Silesia and Pomerania, while Western Allies entered Western Germany and closed to the Rhine river. By March, the Western Allies crossed the Rhine north and south of the Ruhr, encircling the German Army Group B,[255] while the Soviets advanced to Vienna. In early April, the Western Allies finally pushed forward in Italy and swept across Western Germany, while Soviet and Polish forces stormed Berlin in late April. The American and Soviet forces linked up on Elbe river on 25 April. On 30 April 1945, the Reichstag was captured, signalling the military defeat of the Third Reich.[256]

Several changes in leadership occurred during this period. On 12 April, President Roosevelt died and was succeeded by Harry Truman. Benito Mussolini was killed by Italian partisans on 28 April.[257] Two days later, Hitler committed suicide, and was succeeded by Grand Admiral Karl Dönitz.[258]
The German Reichstag after its capture by the Allies, 3 June 1945

German forces surrendered in Italy on 29 April. Total and unconditional surrender was signed on 7 May, to be effective by the end of 8 May.[259] German Army Group Centre resisted in Prague until 11 May.[260]

In the Pacific theatre, American forces accompanied by the forces of the Philippine Commonwealth advanced in the Philippines, clearing Leyte by the end of April 1945. They landed on Luzon in January 1945 and captured Manila in March following a battle which reduced the city to ruins. Fighting continued on Luzon, Mindanao, and other islands of the Philippines until the end of the war.[261] On the night of 9–10 March, B-29 bombers of the US Army Air Forces struck Tokyo with incendiary bombs, which killed 100,000 people within a few hours. Over the next five months, American bombers firebombed 66 other Japanese cities, causing the destruction of untold numbers of buildings and the deaths of between 350,000–500,000 Japanese civilians.[262]
Japanese foreign affairs minister Mamoru Shigemitsu signs the Japanese Instrument of Surrender on board the USS Missouri, 2 September 1945

In May 1945, Australian troops landed in Borneo, over-running the oilfields there. British, American, and Chinese forces defeated the Japanese in northern Burma in March, and the British pushed on to reach Rangoon by 3 May.[263] Chinese forces started to counterattack in Battle of West Hunan that occurred between 6 April and 7 June 1945. American forces also moved towards Japan, taking Iwo Jima by March, and Okinawa by the end of June.[264] At the same time American bombers were destroying Japanese cities, American submarines cut off Japanese imports, drastically reducing Japan's ability to supply its overseas forces.[265]

On 11 July, Allied leaders met in Potsdam, Germany. They confirmed earlier agreements about Germany,[266] and reiterated the demand for unconditional surrender of all Japanese forces by Japan, specifically stating that "the alternative for Japan is prompt and utter destruction".[267] During this conference, the United Kingdom held its general election, and Clement Attlee replaced Churchill as Prime Minister.[268]

As Japan continued to ignore the Potsdam terms issued to them on 27 July, the United States dropped atomic bombs on the Japanese cities of Hiroshima and Nagasaki in early August. Like the Japanese cities previously bombed by American airmen, the US and its allies justified the atomic bombings as military necessity to avoid invading the Japanese home islands which would cost the lives of between 250,000–500,000 Allied troops and millions of Japanese troops and civilians.[269] Between the two bombings, the Soviets, pursuant to the Yalta agreement, invaded Japanese-held Manchuria, and quickly defeated the Kwantung Army, which was the largest Japanese fighting force.[270][271] The Red Army also captured Sakhalin Island and the Kuril Islands. On 15 August 1945, Japan surrendered, with the surrender documents finally signed aboard the deck of the American battleship USS Missouri on 2 September 1945, ending the war.[272]
Aftermath
Main articles: Aftermath of World War II and Consequences of Nazism
Ruins of Warsaw in January 1945, after the deliberate destruction of the city by the occupying German forces
Post-war Soviet territorial expansion; resulted in Central European border changes, the creation of a Communist Bloc, and start of the Cold War

The Allies established occupation administrations in Austria and Germany. The former became a neutral state, non-aligned with any political bloc. The latter was divided into western and eastern occupation zones controlled by the Western Allies and the USSR, accordingly. A denazification program in Germany led to the prosecution of Nazi war criminals and the removal of ex-Nazis from power, although this policy moved towards amnesty and re-integration of ex-Nazis into West German society.[273]

Germany lost a quarter of its pre-war (1937) territory. Among the eastern territories, Silesia, Neumark and most of Pomerania were taken over by Poland, East Prussia was divided between Poland and the USSR, followed by the expulsion of the 9 million Germans from these provinces, as well as the expulsion of 3 million Germans from the Sudetenland in Czechoslovakia to Germany. By the 1950s, every fifth West German was a refugee from the east. The Soviet Union also took over the Polish provinces east of the Curzon line, from which 2 million Poles were expelled;[274] north-east Romania,[275][276] parts of eastern Finland,[277] and the three Baltic states were also incorporated into the USSR.[278][279]

In an effort to maintain peace,[280] the Allies formed the United Nations, which officially came into existence on 24 October 1945,[281] and adopted the Universal Declaration of Human Rights in 1948, as a common standard for all member nations.[282] The great powers that were the victors of the war—the United States, Soviet Union, China, Britain, and France—formed the permanent members of the UN's Security Council.[7] The five permanent members remain so to the present, although there have been two seat changes, between the Republic of China and the People's Republic of China in 1971, and between the Soviet Union and its successor state, the Russian Federation, following the dissolution of the Soviet Union. The alliance between the Western Allies and the Soviet Union had begun to deteriorate even before the war was over.[283]

Germany had been de facto divided, and two independent states, the Federal Republic of Germany and the German Democratic Republic[284] were created within the borders of Allied and Soviet occupation zones, accordingly. The rest of Europe was also divided into Western and Soviet spheres of influence.[285] Most eastern and central European countries fell into the Soviet sphere, which led to establishment of Communist-led regimes, with full or partial support of the Soviet occupation authorities. As a result, Poland, Hungary, East Germany,[286] Czechoslovakia, Romania, and Albania[287] became Soviet satellite states. Communist Yugoslavia conducted a fully independent policy, causing tension with the USSR.[288]

Post-war division of the world was formalised by two international military alliances, the United States-led NATO and the Soviet-led Warsaw Pact;[289] the long period of political tensions and military competition between them, the Cold War, would be accompanied by an unprecedented arms race and proxy wars.[290]

In Asia, the United States led the occupation of Japan and administrated Japan's former islands in the Western Pacific, while the Soviets annexed Sakhalin and the Kuril Islands.[291] Korea, formerly under Japanese rule, was divided and occupied by the US in the South and the Soviet Union in the North between 1945 and 1948. Separate republics emerged on both sides of the 38th parallel in 1948, each claiming to be the legitimate government for all of Korea, which led ultimately to the Korean War.[292]

In China, nationalist and communist forces resumed the civil war in June 1946. Communist forces were victorious and established the People's Republic of China on the mainland, while nationalist forces retreated to Taiwan in 1949.[293] In the Middle East, the Arab rejection of the United Nations Partition Plan for Palestine and the creation of Israel marked the escalation of the Arab-Israeli conflict. While European colonial powers attempted to retain some or all of their colonial empires, their losses of prestige and resources during the war rendered this unsuccessful, leading to decolonisation.[294][295]

The global economy suffered heavily from the war, although participating nations were affected differently. The US emerged much richer than any other nation; it had a baby boom and by 1950 its gross domestic product per person was much higher than that of any of the other powers and it dominated the world economy.[296] The UK and US pursued a policy of industrial disarmament in Western Germany in the years 1945–1948.[297] Due to international trade interdependencies this led to European economic stagnation and delayed European recovery for several years.[298][299]

Recovery began with the mid-1948 currency reform in Western Germany, and was sped up by the liberalisation of European economic policy that the Marshall Plan (1948–1951) both directly and indirectly caused.[300][301] The post-1948 West German recovery has been called the German economic miracle.[302] Italy also experienced an economic boom[303] and the French economy rebounded.[304] By contrast, the United Kingdom was in a state of economic ruin,[305] and although it received a quarter of the total Marshall Plan assistance, more than any other European country,[306] continued relative economic decline for decades.[307]

The Soviet Union, despite enormous human and material losses, also experienced rapid increase in production in the immediate post-war era.[308] Japan experienced incredibly rapid economic growth, becoming one of the most powerful economies in the world by the 1980s.[309] China returned to its pre-war industrial production by 1952.[310]
Impact
Casualties and war crimes
Main articles: World War II casualties, War crimes during World War II, War crimes in occupied Poland during World War II, German war crimes, War crimes of the Wehrmacht, Japanese war crimes, Allied war crimes during World War II and Soviet war crimes
World War II deaths

Estimates for the total casualties of the war vary, because many deaths went unrecorded. Most suggest that some 75 million people died in the war, including about 20 million military personnel and 40 million civilians.[311][312][313] Many of the civilians died because of deliberate genocide, massacres, mass-bombing, disease, and starvation.

The Soviet Union lost around 27 million people during the war,[314] including 8.7 million military and 19 million civilian deaths. The largest portion of military dead were 5.7 million ethnic Russians, followed by 1.3 million ethnic Ukrainians.[315] A quarter of the people in the Soviet Union were wounded or killed.[316] Germany sustained 5.3 million military losses, mostly on the Eastern Front and during the final battles in Germany.[317]

Of the total deaths in World War II, approximately 85 percent—mostly Soviet and Chinese—were on the Allied side and 15 percent on the Axis side. Many of these deaths were caused by war crimes committed by German and Japanese forces in occupied territories. An estimated 11[318] to 17 million[319] civilians died as a direct or indirect result of Nazi ideological policies, including the systematic genocide of around 6 million Jews during the Holocaust, along with a further 5 to 6 million ethnic Poles and other Slavs (including Ukrainians and Belarusians)[320]—Roma, homosexuals, and other ethnic and minority groups.[319]
Chinese civilians being buried alive by soldiers of the Imperial Japanese Army, during the Nanking Massacre, December 1937

Roughly 7.5 million civilians died in China under Japanese occupation.[321] Hundreds of thousands (varying estimates) of ethnic Serbs, along with gypsies and Jews, were murdered by the Axis-aligned Croatian Ustaše in Yugoslavia,[322] with retribution-related killings of Croatian civilians just after the war ended.

The best-known Japanese atrocity was the Nanking Massacre, in which several hundred thousand Chinese civilians were raped and murdered.[323] Between 3 million to more than 10 million civilians, mostly Chinese, were killed by the Japanese occupation forces.[324] Mitsuyoshi Himeta reported 2.7 million casualties occurred during the Sankō Sakusen. General Yasuji Okamura implemented the policy in Heipei and Shantung.[325]

Axis forces employed biological and chemical weapons. The Imperial Japanese Army used a variety of such weapons during their invasion and occupation of China (see Unit 731)[326][327] and in early conflicts against the Soviets.[328] Both the Germans and Japanese tested such weapons against civilians[329] and, sometimes on prisoners of war.[330]

The Soviet Union was responsible for the Katyn massacre of 22,000 Polish officers,[331] and the imprisonment or execution of thousands of political prisoners by the NKVD,[332] in the Baltic states, and eastern Poland annexed by the Red Army.

The mass-bombing of civilian areas, notably the cities of Warsaw, Rotterdam and London; including the aerial targeting of hospitals and fleeing refugees[333] by the German Luftwaffe, along with the bombing of Tokyo, and German cities of Dresden, Hamburg and Cologne by the Western Allies may be considered as war crimes. The latter resulted in the destruction of more than 160 cities and the deaths of more than 600,000 German civilians.[334] However, no positive or specific customary international humanitarian law with respect to aerial warfare existed before or during World War II.[335]
Concentration camps, slave labour, and genocide
Further information: Genocide, The Holocaust, Nazi concentration camps, Extermination camp, Forced labour under German rule during World War II, Kidnapping of children by Nazi Germany and Nazi human experimentation
Female SS camp guards remove bodies from lorries and carry them to a mass grave, inside the German Bergen-Belsen concentration camp, 1945

The German Government led by Adolf Hitler and the Nazi Party was responsible for the Holocaust, the killing of approximately 6 million Jews (overwhelmingly Ashkenazim), as well as 2.7 million ethnic Poles,[336] and 4 million others who were deemed "unworthy of life" (including the disabled and mentally ill, Soviet prisoners of war, homosexuals, Freemasons, Jehovah's Witnesses, and Romani) as part of a programme of deliberate extermination. About 12 million, most of whom were Eastern Europeans, were employed in the German war economy as forced labourers.[337]

In addition to Nazi concentration camps, the Soviet gulags (labour camps) led to the death of citizens of occupied countries such as Poland, Lithuania, Latvia, and Estonia, as well as German prisoners of war (POWs) and even Soviet citizens who had been or were thought to be supporters of the Nazis.[338] Sixty percent of Soviet POWs of the Germans died during the war.[339] Richard Overy gives the number of 5.7 million Soviet POWs. Of those, 57 percent died or were killed, a total of 3.6 million.[340] Soviet ex-POWs and repatriated civilians were treated with great suspicion as potential Nazi collaborators, and some of them were sent to the Gulag upon being checked by the NKVD.[341]
Prisoner identity photograph taken by the German SS of a fourteen year old Polish girl, sent as forced labour to Auschwitz, December 1942

Japanese prisoner-of-war camps, many of which were used as labour camps, also had high death rates. The International Military Tribunal for the Far East found the death rate of Western prisoners was 27.1 percent (for American POWs, 37 percent),[342] seven times that of POWs under the Germans and Italians.[343] While 37,583 prisoners from the UK, 28,500 from the Netherlands, and 14,473 from United States were released after the surrender of Japan, the number for the Chinese was only 56.[344]

According to historian Zhifen Ju, at least five million Chinese civilians from northern China and Manchukuo were enslaved between 1935 and 1941 by the East Asia Development Board, or Kōain, for work in mines and war industries. After 1942, the number reached 10 million.[345] The US Library of Congress estimates that in Java, between 4 and 10 million romusha (Japanese: "manual laborers"), were forced to work by the Japanese military. About 270,000 of these Javanese labourers were sent to other Japanese-held areas in South East Asia, and only 52,000 were repatriated to Java.[346]

On 19 February 1942, Roosevelt signed Executive Order 9066, interning about 100,000 Japanese living on the West Coast. Canada had a similar program.[347][348] In addition, 14,000 German and Italian citizens who had been assessed as being security risks were also interned.[349]

In accordance with the Allied agreement made at the Yalta Conference millions of POWs and civilians were used as forced labour by the Soviet Union.[350] In Hungary's case, Hungarians were forced to work for the Soviet Union until 1955.[351]
Occupation
Main articles: German-occupied Europe, Lebensraum, Untermensch, Collaboration with the Axis Powers during World War II, Resistance during World War II and Nazi plunder
Blindfolded Polish citizens just before execution by German soldiers in Palmiry, 1940

In Europe, occupation came under two forms. In Western, Northern and Central Europe (France, Norway, Denmark, the Low Countries, and the annexed portions of Czechoslovakia) Germany established economic policies through which it collected roughly 69.5 billion reichmarks (27.8 billion US Dollars) by the end of the war, this figure does not include the sizeable plunder of industrial products, military equipment, raw materials and other goods.[352] Thus, the income from occupied nations was over 40 percent of the income Germany collected from taxation, a figure which increased to nearly 40 percent of total German income as the war went on.[353]

In the East, the much hoped for bounties of Lebensraum were never attained as fluctuating front-lines and Soviet scorched earth policies denied resources to the German invaders.[354] Unlike in the West, the Nazi racial policy encouraged excessive brutality against what it considered to be the "inferior people" of Slavic descent; most German advances were thus followed by mass executions.[355] Although resistance groups did form in most occupied territories, they did not significantly hamper German operations in either the East[356] or the West[357] until late 1943.

In Asia, Japan termed nations under its occupation as being part of the Greater East Asia Co-Prosperity Sphere, essentially a Japanese hegemony which it claimed was for purposes of liberating colonised peoples.[358] Although Japanese forces were originally welcomed as liberators from European domination in some territories, their excessive brutality turned local public opinions against them within weeks.[359] During Japan's initial conquest it captured 4,000,000 barrels (640,000 m3) of oil (~5.5×105 tonnes) left behind by retreating Allied forces, and by 1943 was able to get production in the Dutch East Indies up to 50 million barrels (~6.8×106 t), 76 percent of its 1940 output rate.[359]
Home fronts and production
Main articles: Military production during World War II and Home front during World War II
Allied to Axis GDP ratio

In Europe, before the outbreak of the war, the Allies had significant advantages in both population and economics. In 1938, the Western Allies (United Kingdom, France, Poland and British Dominions) had a 30 percent larger population and a 30 percent higher gross domestic product than the European Axis (Germany and Italy); if colonies are included, it then gives the Allies more than a 5:1 advantage in population and nearly 2:1 advantage in GDP.[360] In Asia at the same time, China had roughly six times the population of Japan, but only an 89 percent higher GDP; this is reduced to three times the population and only a 38 percent higher GDP if Japanese colonies are included.[360]

Though the Allies' economic and population advantages were largely mitigated during the initial rapid blitzkrieg attacks of Germany and Japan, they became the decisive factor by 1942, after the United States and Soviet Union joined the Allies, as the war largely settled into one of attrition.[361] While the Allies' ability to out-produce the Axis is often attributed to the Allies having more access to natural resources, other factors, such as Germany and Japan's reluctance to employ women in the labour force,[362] Allied strategic bombing,[363] and Germany's late shift to a war economy[364] contributed significantly. Additionally, neither Germany nor Japan planned to fight a protracted war, and were not equipped to do so.[365] To improve their production, Germany and Japan used millions of slave labourers;[366] Germany used about 12 million people, mostly from Eastern Europe,[337] while Japan used more than 18 million people in Far East Asia.[345][346]
Advances in technology and warfare
Main article: Technology during World War II
Nuclear "gadget" being raised to the top of the detonation tower, at Alamogordo Bombing Range; Trinity nuclear test, July 1945

Aircraft were used for reconnaissance, as fighters, bombers, and ground-support, and each role was advanced considerably. Innovation included airlift (the capability to quickly move limited high-priority supplies, equipment, and personnel);[367] and of strategic bombing (the bombing of enemy industrial and population centres to destroy the enemy's ability to wage war).[368] Anti-aircraft weaponry also advanced, including defences such as radar and surface-to-air artillery, such as the German 88 mm gun. The use of the jet aircraft was pioneered and, though late introduction meant it had little impact, it led to jets becoming standard in worldwide air forces.[369]

Advances were made in nearly every aspect of naval warfare, most notably with aircraft carriers and submarines. Although aeronautical warfare had relatively little success at the start of the war, actions at Taranto, Pearl Harbor, and the Coral Sea established the carrier as the dominant capital ship in place of the battleship.[370][371][372]
A V-2 rocket launched from a fixed site in Peenemünde, 1943

In the Atlantic, escort carriers proved to be a vital part of Allied convoys, increasing the effective protection radius and helping to close the Mid-Atlantic gap.[373] Carriers were also more economical than battleships due to the relatively low cost of aircraft[374] and their not requiring to be as heavily armoured.[375] Submarines, which had proved to be an effective weapon during the First World War[376] were anticipated by all sides to be important in the second. The British focused development on anti-submarine weaponry and tactics, such as sonar and convoys, while Germany focused on improving its offensive capability, with designs such as the Type VII submarine and wolfpack tactics.[377] Gradually, improving Allied technologies such as the Leigh light, hedgehog, squid, and homing torpedoes proved victorious.

Land warfare changed from the static front lines of World War I to increased mobility and combined arms. The tank, which had been used predominantly for infantry support in the First World War, had evolved into the primary weapon.[378] In the late 1930s, tank design was considerably more advanced than it had been during World War I,[379] and advances continued throughout the war with increases in speed, armour and firepower.

At the start of the war, most commanders thought enemy tanks should be met by tanks with superior specifications.[380] This idea was challenged by the poor performance of the relatively light early tank guns against armour, and German doctrine of avoiding tank-versus-tank combat. This, along with Germany's use of combined arms, were among the key elements of their highly successful blitzkrieg tactics across Poland and France.[378] Many means of destroying tanks, including indirect artillery, anti-tank guns (both towed and self-propelled), mines, short-ranged infantry antitank weapons, and other tanks were utilised.[380] Even with large-scale mechanisation, infantry remained the backbone of all forces,[381] and throughout the war, most infantry were equipped similarly to World War I.[382]

The portable machine gun spread, a notable example being the German MG34, and various submachine guns which were suited to close combat in urban and jungle settings.[382] The assault rifle, a late war development incorporating many features of the rifle and submachine gun, became the standard postwar infantry weapon for most armed forces.[383][384]

Most major belligerents attempted to solve the problems of complexity and security involved in using large codebooks for cryptography by designing ciphering machines, the most well known being the German Enigma machine.[385] Development of SIGINT (signals intelligence) and cryptanalysis enabled the countering process of decryption. Notable examples were the Allied decryption of Japanese naval codes[386] and British Ultra, a pioneering method for decoding Enigma benefiting from information given to Britain by the Polish Cipher Bureau, which had been decoding early versions of Enigma before the war.[387] Another aspect of military intelligence was the use of deception, which the Allies used to great effect, such as in operations Mincemeat and Bodyguard.[386][388] Other technological and engineering feats achieved during, or as a result of, the war include the world's first programmable computers (Z3, Colossus, and ENIAC), guided missiles and modern rockets, the Manhattan Project's development of nuclear weapons, operations research and the development of artificial harbours and oil pipelines under the English Channel.[389]

4817
The Flood / Re: #ChimpOut2014
« on: November 25, 2014, 11:54:43 PM »

4818
The Flood / Re: I got raped tonight
« on: November 25, 2014, 11:48:13 PM »
Sometimes I wish I were raped...



by an attractive person..

I'm so sorry you get raped by ugly people.

4819
The Flood / Re: Guess where I'm at?
« on: November 25, 2014, 10:55:15 PM »
SHIT ON THE STEPS OF CRONY BUREAUCRATIC CAPITALISM IN THE NAME OF MIKE BROWN

HANDS UP DONT SHOOT

4820
The Flood / Re: Slash is...
« on: November 25, 2014, 10:47:19 PM »
oh bby

4821
The Flood / Re: I love big titties
« on: November 25, 2014, 10:36:51 PM »
well since Death posted big meaty tits, I will too. Sizes may vary.

NSFW of course

Spoiler
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Disregard, 80% of the girls look like men, and all of them have terribly saggy, stupidly large watermelon tits that look really bad
>he doesn't like huge tits



>Has never touched a pair of boobs

I speak from experience, watchu got? Orite digital whale tits and lotion

4822
The Flood / Re: That's it, I'm leaving
« on: November 25, 2014, 10:21:50 PM »
I still think it's totally okay to marry them though

Yeah, get em' right outta the womb!

4823
Spoiler porn

4824
The Flood / Re: I love big titties
« on: November 25, 2014, 10:17:56 PM »
well since Death posted big meaty tits, I will too. Sizes may vary.

NSFW of course

Spoiler
Spoiler
Spoiler
Spoiler
Spoiler
Spoiler

Spoiler
Spoiler

Disregard, 80% of the girls look like men, and all of them have terribly saggy, stupidly large watermelon tits that look really bad

4825
The Flood / Re: That's it, I'm leaving
« on: November 25, 2014, 10:15:57 PM »
What, running back to the daycare center already?

4826
The Flood / Re: I don't fucking understand women
« on: November 25, 2014, 10:07:09 PM »
FUCK HER RIGHT IN THE PUSSY

4827
The Flood / Re: Brazilians are the proof that..
« on: November 25, 2014, 09:42:18 PM »
Niggers are proof that slavery wasn't enough

4828
The Flood / Re: Bill cosby is a serial rapist! articles inside.
« on: November 25, 2014, 09:17:56 PM »
YouTube


>Be a fat ugly cunt
>Accuse a celebrity of rape

4829
The Flood / Re: I love big titties
« on: November 25, 2014, 09:04:23 PM »
I'm more of a butt guy
Me too, but in 18 years of life, I have come to accept that both are great, and I love big titties.

Its funny cuz you havent touched big titties

4830
The Flood / Re: Black man angry at Ferguson Trials
« on: November 25, 2014, 08:48:14 PM »
lol he can stay mad, it won't change the ruling

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