Quote from: BaconShelf on May 02, 2017, 05:23:21 AMGood question; how do we define "up" in a 3D universe? On Earth, we traditionally use the sky to mean "up", but the Earth is a sphere. We could use the ecliptic of the Solar System, which in turn is derived from the ecliptic of the Milky Way but even then, how do we define which side is up or down? Stars in the north could be used, but they come from the separation of hemispheres based on magnetic fields and the locations of who was making the maps in question.And while the milky has a galactic plane, what about the local group? Does the universe itself have an ecliptic? Can there be a definitive up and down? What about in other dimensions? Can a fifth dimensional universe have an up? Truly a fascinating question.He was clearly just asking about the critically acclaimed 2009 Disney Pixar movie "Up", in which an unlikely duo goes on an incredible adventure in a floating house.
Good question; how do we define "up" in a 3D universe? On Earth, we traditionally use the sky to mean "up", but the Earth is a sphere. We could use the ecliptic of the Solar System, which in turn is derived from the ecliptic of the Milky Way but even then, how do we define which side is up or down? Stars in the north could be used, but they come from the separation of hemispheres based on magnetic fields and the locations of who was making the maps in question.And while the milky has a galactic plane, what about the local group? Does the universe itself have an ecliptic? Can there be a definitive up and down? What about in other dimensions? Can a fifth dimensional universe have an up? Truly a fascinating question.