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You can't. See "Simulating Physics With Computers," linked here: https://twitter.com/theshawwn/status/1394159744139632640 https://twitter.com/theshawwn/status/1

You can't. See "Simulating Physics With Computers," linked here: https://twitter.com/theshawwn/status/1394159744139632640 https://twitter.com/theshawwn/status/1394159744139632640 And some thoughts on the limitations with respect to creating AGI: https://twitter.com/theshawwn/status/1446261451061145602 https://twitter.com/theshawwn/status/1446261451061145602 See section 5, "Can quantum systems be probabilistically simulated by a classical computer?" > The probability that they match is eight-tenths, the probability that they mismatch is plus two-tenths; every physical probability comes out positive. But the original f's are not positive, and therein lies the great difficulty. The only difference between a probabilistic classical world and the equations of the quantum world is that somehow or other it appears as if the probabilities would have to go negative, and that we do not know, as far as I know, how to simulate. Okay, that's the fundamental problem. I don't know the answer to it, but I wanted to explain that if I try my best to make the equations look as near as possible to what would be imitable by a classical probabilistic computer, I get into trouble. When I was younger and only slightly more foolish, I wanted to spend a lot of time researching this to see if there was a way around the problem. I quickly realized that perhaps I should focus on adding value in a field that I was good at. :) Maybe one of you can try, since the only alternative is to take Feynman at his word.

aeternum 5y ago
The claim that discretization is not equal to quantization is a key claim and I'm not sure the paper actually proves/shows this. If it turns out that spacetime is discrete and not continuous then we should be able to simulate it. The possible states of some chunk of spacetime (given some maximum/known energy) would be non-infinite and even though it might take us years to calculate each time-step, we could still make progress. I've seen the theory kicked around before, but why couldn't the universe basically consist of plank length sized voxels and a similarly small update timestep? It would still look plenty continuous to us.
- sillysaurusx 5y ago
  It’s because of the anisotropy. Suppose the universe was a regular grid of voxels. You could run experiments to prove that. I don’t understand the details, but that was Feynman’s counter argument. (See the “messenger lectures” series on YouTube.) If the grid isn’t regular, you run into other problems. But iirc at one point Feynman was toying with the idea that the grid might be randomly distributed.

aeternum 5y ago

The claim that discretization is not equal to quantization is a key claim and I'm not sure the paper actually proves/shows this. If it turns out that spacetime is discrete and not continuous then we should be able to simulate it. The possible states of some chunk of spacetime (given some maximum/known energy) would be non-infinite and even though it might take us years to calculate each time-step, we could still make progress. I've seen the theory kicked around before, but why couldn't the universe basically consist of plank length sized voxels and a similarly small update timestep? It would still look plenty continuous to us.

sillysaurusx 5y ago
It’s because of the anisotropy. Suppose the universe was a regular grid of voxels. You could run experiments to prove that. I don’t understand the details, but that was Feynman’s counter argument. (See the “messenger lectures” series on YouTube.) If the grid isn’t regular, you run into other problems. But iirc at one point Feynman was toying with the idea that the grid might be randomly distributed.