Even In A Quantum Universe, Space And Time Might Be Continuous, Not Discrete
“In General Relativity, matter and energy tell space how to curve, while curved space tells matter and energy how to move. But in General Relativity, space and time are continuous and non-quantized. All the other forces are known to be quantum in nature, and require a quantum description to match reality. We assume and suspect that gravitation is fundamentally quantum, too, but we aren’t sure. Furthermore, if gravity is ultimately quantum, we don’t know whether space and time remain continuous, or whether they become fundamentally discrete.
Quantum doesn’t necessarily mean that every property breaks down into an indivisible chunk. In conventional quantum field theory, spacetime is the stage upon which the various quanta act out the play of the Universe. At the core of it all should be a quantum theory of gravity. Until we can determine whether space and time are discrete, continuous, or unavoidably blurred, we cannot know our Universe’s nature at a fundamental level.”
If you could look at the Universe down to the smallest possible scales, fundamentally, what would you find? Would you discover that space and time really could be broken up into tiny, indivisible entities where the was a length scale and a timescale that could be divided no further? Would you discover that space and time were quantum in nature, but were instead a continuous fabric? Or would you discover something else, like that space and time weren’t quantum or that there was a fundamental “blurring” that prevented you from seeing below a specific scale?