There is a theory that describes space-time at the quantum level as a ten-dimensional space with a complex shape:
A Calabi–Yau manifold, also known as a Calabi–Yau space, is a special type of manifold that is described in certain branches of mathematics such as algebraic geometry. The Calabi–Yau manifold’s properties, such as Ricci flatness, also yield applications in theoretical physics. Particularly in superstring theory, the extra dimensions of spacetime are sometimes conjectured to take the form of a 6-dimensional Calabi–Yau manifold, which led to the idea of mirror symmetry.
This space is “open” in the 3 dimensions plus time we perceive, but rolled up in the other six dimensions so that strings and membranes on the order of Planck length (10^-33 meters) can vibrate, creating all the known particles of the Standard Model and then some.
There are other models.
Julian Barbour (“The End of Time”) describes an N-space sprinkled with probability streams, so that nearby spaces (in terms of similar physics) are more probably than more remote regions. Time becomes invisible in this ultimate reality.
Lisa Randall (“Warped Passages”) describes a quantum world of ten-space “branes” which impinge on each other and exchange of energies, such as gravity.
I have followed the idea that time and space are quantized, which seems to resolve several issues where the math reveals infinities and gauge transforms are not useful. In that scenario, the perceivable things are not basic, they are “emergent properties” of the quantum nature of things. As an illustration of an emergent property, if you look at the molecules of air trapped in a container, all you see is randomly bouncing blobs. However, en masse they have properties of pressure, temperature and entropy changes which are invisible at the molecular level.