Matt, do not get wrapped up into space time, space time only exists has a concept, it only exists between two points of mass, it is a virtual navigation system to represent journeys that have not been taken. XYZ only exists of matter and time only exists of matter, space time is a n-dimensional  5th dimension solution to a problem, no more no less.

X, Y, Z & T are names that we give to dimensions of the space and time that exist in our imaginations. We can carve those names into physical objects, like graph paper, in the real space-time that hosts the atoms we're made of; or we may type the names of coordinate axes into a computer program, where they control how data are stored in a microprocessor's transistors, as well as how the data are presented on a screen or in a VR helmet.

Now, if you had a VR helmet and a haptic feedback suit, you could make a pretty good match between the virtual space-time in the computer and the real space-time in which your body exists. You could even take that to the extreme and be absorbed into the Matrix. But the two space-times would still not be identical.

So we have this virtual space-time programmed into a computer, complete with Einstein's relativity, occupied by low-res digital imitations of whatever galaxies SDSS has mapped in 3D. We can zoom out to view our virtual observable universe as seen by a hypothetical viewer anywhere in the mapped region (bearing in mind that our view of distant galaxies may be a few billion years old, and an observer there would be seeing our galaxy as it was billions of years ago). We look thru our virtual Hubble space-telescope into our virtual universe; then we compare what we see there to what the real HST sees in the real universe . If we see discrepancies, we can tweak our virtual universe.

We can also zoom in on a virtual atomic nucleus in our virtual universe. But the picture in there is a blur because we can't resolve time or space that closely in the real universe. We are free to invent models which can be resolved arbitrarily small in both space and time. But we can only predict real world outcomes statistically. If the model predicts probable outcomes which are not a good statistical match to what the LHC detects, the model needs to be tweaked.