Assumption 3 is faulty.
You can, of course, represents parts of the universe like Google maps. But there are 3 limits to the precision with which you can emulate those parts.
- Heisenberg uncertainty principle
- Computational power limit
- Unsolvable math
The first puts a limit (and note it is a mathematical limit) to the precision on coupled quantities of a quantum particle. So, even if we had enough power to compute, let’s say, our solar system in terms of particles, the emulation will diverge from the actual solar system.
As for the second: I doubt you can use a q-bit to emulate more than a quantum particle quantity. This means that to emulate our solar system we need at least as many particles as there are in the solar system. Probably much more.
Of course it very different what Google maps does: that is a simplified model of the Earth surface. This is already in progress: https://edition.cnn.com/2020/07/22/world/universe-3d-map-intl-hnk-scn-scli/index.html
3. Even though we have equations to predict statistically the interaction between particles, we don’t know how to solve these equations with complex systems. Often we know only the solution one or two items. For example we know a lot about 1 black hole, put 2 black holes one near the other and the math gets very complicated…
