Hacking the simulation to do time travel (with quantum computers?)

Question

I am trying to come up with a plausible speculative physics explanation for a story I am writing where the conceit is that phsyicists discover the universe is a simulation. The idea is that the simulation is reset to a particular time in the past (assuming there is some way the base universe computer knows what it was then), except that a specific volume of space surrounding the time traveler in isn't. This has the effect of destroying the present universe (and everyone in it) and restarting it.

Question: What do you think of my current below explanation? Can it be improved?

My answer: Scientists discover that our universe is indeed the result of a simulator in a more complex (base) universe simulating a simpler universe (akin to us living in 3d simulating a 2d or 1d world) and quantum mechanics is some optimisation technique to make it easier for the base universe to compute our reality. We in the simulated universe then discover how to hack it. The way we do this is that a branch of quantum computing develops to explore weird artifacts / patterns in the superpositions that has something to do with the Mandlebrot set (the weird artifacts). Realising that this might be the artefact of our simulation being rendered by another more complex universe, the scientists try to discover more about how the software of the universe works by probing these artefacts. They do this by asking specific questions in the quantum computer (or other quantumy things) and use deep learning networks to encode the data. By doing this for long enough and giving the neural net the ability to run its own quantum experiments, the neural net figures out the architecture of the base reality enough to be able to transfer its knowledge of the codebase of our universe to being able to hack it somehow.

I assume that sims can affect hardware in the real world. For instance, if in some far future on Earth we create self-aware sims and they figure out that they are running on a computer, they could try to crash the computer by, for instance, doing lots of processor intensive tasks that might cause the computer to overheat and crash the computer.

I’m also assuming that the true nature of base reality physics is far beyond human comprehension so only massive amounts of experiments and self-learning by a massive neural net is possible to understand whatever is really there).

Does any of this idea seem believable given the concepts involved, or am I wholly misunderstanding some things? How could you tweak it?

What speculative physics would you suggest is best for this story concept? It's key that the time travel element occur by means of restarting the simulation. A key story element is that some characters really don't want the time travel device to work as it will end up killing them and everyone they know. Also, the discovery the world is a simulation has interesting implications for religion. Finally, I am wondering what else one could do if this was all possible? e.g. could the universe be made of voxels and hackers could switch them on and off etc. Ideally I want hacking to be possible with tech that could conceivably be done within the next 50 years.

If anyone has better ideas of how to accomplish this task, or it's been thought of before, very grateful!

Answer 1

Reproduce the simulation on your computer and run it faster. Predict the future.

Hacking your own running simulation is like tinkering with the plane you are flying in. You would want to have a very good reason because there are a lot of outcomes which lead you you not flying any more.

Similarly hacking your own reality. If you change it you may be unable to go back because there will be no you.

But once you understand the sim you can reproduce it and model it. If I am a Sim and I can set up my version of The Sims to reproduce my current state of things, I can then run the model 100x faster, tweak the model to introduce a difference then see what the future brings. I can run multiple simulations and not mess with my own reality until I know exactly what will work. Then I can mess with it in the regular ways; nothing quantum and spooky.

For example you could test various interventions for global warming and see which one worked best, which ones don't work and which lead to disaster, then set out doing the one that works best.

It might be possible to understand the past by running your sim at negative speed to see the state of things at some prior time that led to your current state.

---

Knowing the future and knowing the past for the benefit of human kind will be the big picture that the bosses are working on. I normally bring those people coffee and sometimes pizza but I have some smarts too. I will come in after hours to use the model and determine how I can become a rock and roll star. It involves having pants that are tight which is the easiest part for me.

Answer 2

Memory Overflow

aka " Uh-oh Morty, this crowd looks too small for one of our famous rap concerts! I don't think we can perform our new song 'The Recipe for Concentrated Dark Matter' for a crowd this tiny!"

Everyone knows the quantum hack is too complex for humans to get their head around. We have enough trouble understanding quantum mechanics in the first place.

Fortunately quantum computers don't need to understand quantum mechanics. They just need to be programmed with the rules of interaction in mind.

Fortunately (again) we don't even need to program our computers. We use a neural net for that. A quantum program on a computer with 1000 Qbits is just 1000 nodes with edges connecting them. Each program is a different assignment of weights to the edges. The weights control how information flows between nodes. The neural net is used to decide the weights.

As you said, quantum mechanics is just an artifact of the simulation, that allows it to save memory by not resolving events (leaving them in superposition form) until absolutely necessary. The hack works in principle by forcing a lot of resolutions over a small space/time frame.

This causes a memory overload. The part of the Big Simulating Computer (BSC) memory that describes the Small Quantum Computer (SQC) then overflows into the adjacent parts of BSC memory. That means the parts of the simulation described by the second block of BSC memory change.

For example if the first segment of memory describes the SQC and the adjacent segment describes an Oak tree on the far side of the planet, then running the program might change the Oak tree into an Ash tree. More likely however the Oak tree will suffer a EXISTENCE FAILURE CLASS 1.

Different programs will have different effects on the tree. Any program a human comes up with will just make the tree collapse into a puddle of quantum data. The Neural net uses trial and error and a lot of classical computing power to learn useful changes to the tree.

The same principle applies to making changes to the entire universe. You just have to find the bit of BSC memory that says what time it is, and use the SQC to replace that bit with whatever time you want it to be, without ruining the rest of the simulation.