I'm sure in the far future we could definitely have the power to simulate an entire universe.An, but not our, thats the point we got.
And still, what would this 'simulation' look like? It would somehow process everything, but would it be something we can still read from?
What is a 'simulation' if not something that is actually less than the original thing. Trying to simulate it 100% would actually mean cloning it, wouldn't it?