In general relativity, the choice of the time dimension
is fairly arbitrary: you can slice spacetime lots of ways. In
quantum gravity, time vanishes entirely as an independent phenomena.
All one has are three-dimensional geometries floating in a superspace.
Arbitrary arrangements of them in near proximity replicates the
appearance of a continuous four-dimensional spacetime; in this
sense the universe we experience as spacetime is a construct of
an ontologically prior but ever present superspace of geometries
lacking time. In turn, such a superspace obeying the laws of quantum
field theory raises the question of its origin and the origin
of its laws. Where do superspace and the laws of nature come from?
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