To John Wheeler, the race to explain time was personal
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Re: To John Wheeler, the race to explain time was personal
#2On observers creating the universe, I’ve sometimes wondered if given the simulation hypothesis, that simulating quantum mechanics is so computationally expensive that it isn’t done unless we’re looking at it, and that the high energy levels required to probe smaller and smaller length scales is an artifact of the computational requirements of simulating it.
Re: To John Wheeler, the race to explain time was personal
#3I was lucky enough to have met John Wheeler when I was in grad school. He was a wonderful man who radiated joy and curiosity.
My favorite anecdote about him, which was not widely known, involved what used to be called "nut letters." Before the internet, if you were a famous scientist, particularly a famous physicist, you would receive actual letters from people all over the world asking for help with their perpetual motion machines, time travel devices, and similar nutty theories. Having worked on black holes, gravity, general relativity, and the bomb, Wheeler was quite a nut magnet. He was also blessed with a bit of OCD in the way he organized and categorized all his notes (his annotated bibliography for Misner Thorne and Wheeler Gravitation filled many shelves in the library). John didn't just receive nut letters. He received, read, organized, filed, classified, and acted on nut letters. His preferred response to them was "I'm afraid I'm not very knowledgeable in the area of your work but I believe you should contact _____ who is working on similar conjectures and may be a good source of additional insights" at which point both parties in that conversation would be so ecstatic to be talking with someone recommended to them by the great John Wheeler that they'd never bother him again. While in grad school, I happened to read an article in the New York Times on a perpetual motion machine (their weekly Science Times section was fantastic but did occasionally step into pseudo science topics). At the end of the article the main researcher thanked John Wheeler for having introduced him to the theorist who had helped him refine his understanding of the mechanisms at play in his invention, and I couldn't help but smile at the wonderful successes of John Wheeler's nut dating service.
Re: To John Wheeler, the race to explain time was personal
#4I was lucky enough to have met John Wheeler when I was in grad school. He was a wonderful man who radiated joy and curiosity. My favorite anecdote about him, which was not widely known, involved what used to be called "nut letters." Before the internet, if you were a famous scientist, particularly a famous physicist, you would receive actual letters from people all over the world asking for help with their perpetual…
My colleagues and I used to get these "nut letters" occasionally even as unknown grad students. They were quite a treat to read: the human imagination is a marvel, and curiosity knows no bounds. If they'd taken slightly different paths than they had, some probably would have even been with my colleagues reading those letters instead of writing them.
Re: To John Wheeler, the race to explain time was personal
#5On observers creating the universe, I’ve sometimes wondered if given the simulation hypothesis, that simulating quantum mechanics is so computationally expensive that it isn’t done unless we’re looking at it, and that the high energy levels required to probe smaller and smaller length scales is an artifact of the computational requirements of simulating it.
That's an interesting thought. It it's true, it seems to have some implications:
* Whoever is running the simulation cares about whether we're looking.
* They had a good reason for going with quantum mechanics rather than something that would be easier to simulate.
I know some people would say that's because they're interested in simulating conscious life and quantum mechanics is essential for consciousness. However, I find it very implausible that quantum mechanics is essential for consciousness so I'd prefer a different hypothesis for why they went with a difficult-to-simulate physics in their simulated universe. Any ideas?
Re: To John Wheeler, the race to explain time was personal
#6On observers creating the universe, I’ve sometimes wondered if given the simulation hypothesis, that simulating quantum mechanics is so computationally expensive that it isn’t done unless we’re looking at it, and that the high energy levels required to probe smaller and smaller length scales is an artifact of the computational requirements of simulating it.
> that simulating quantum mechanics is so computationally expensive that it isn’t done unless we’re looking at it
This is a common misconception. It's more difficult to simulate a quantum system than a classical system. To simulate a classic system you have to simulate one posible state. To simulate a quantum system you must simulate all possible path.
This is the advantage of quantum computers. With the hardware for only N qbits, you can calculate 2^N states (for some very specific problems that are quantum-computer-friendly).
Re: To John Wheeler, the race to explain time was personal
#7On observers creating the universe, I’ve sometimes wondered if given the simulation hypothesis, that simulating quantum mechanics is so computationally expensive that it isn’t done unless we’re looking at it, and that the high energy levels required to probe smaller and smaller length scales is an artifact of the computational requirements of simulating it.
That's an interesting thought. It it's true, it seems to have some implications: * Whoever is running the simulation cares about whether we're looking. * They had a good reason for going with quantum mechanics rather than something that would be easier to simulate. I know some people would say that's because they're interested in simulating conscious life and quantum mechanics is essential for consciousness. However,…
Idea: their reality is much more computationally complex than quantum mechanics, so much so the difference between classical and quantum is irrelevant from a cost point of view and matters only from a results point of view.
Re: To John Wheeler, the race to explain time was personal
#8On observers creating the universe, I’ve sometimes wondered if given the simulation hypothesis, that simulating quantum mechanics is so computationally expensive that it isn’t done unless we’re looking at it, and that the high energy levels required to probe smaller and smaller length scales is an artifact of the computational requirements of simulating it.
> that simulating quantum mechanics is so computationally expensive that it isn’t done unless we’re looking at it This is a common misconception. It's more difficult to simulate a quantum system than a classical system. To simulate a classic system you have to simulate one posible state. To simulate a quantum system you must simulate all possible path. This is the advantage of quantum computers. With the hardware for…
I'm by no means an expert, but how about using Pilot Wave Theory to do the simulation? As I understand, you wouldn't need to simulate an exponential number of states, you just simulate the pilot wave.
See also (very accessible): https://www.quora.com/Why-dont-more-physicists-subscribe-to-...
Re: To John Wheeler, the race to explain time was personal
#9On observers creating the universe, I’ve sometimes wondered if given the simulation hypothesis, that simulating quantum mechanics is so computationally expensive that it isn’t done unless we’re looking at it, and that the high energy levels required to probe smaller and smaller length scales is an artifact of the computational requirements of simulating it.
That's an interesting thought. It it's true, it seems to have some implications: * Whoever is running the simulation cares about whether we're looking. * They had a good reason for going with quantum mechanics rather than something that would be easier to simulate. I know some people would say that's because they're interested in simulating conscious life and quantum mechanics is essential for consciousness. However,…
Maybe because quantum mechanics has interesting dynamics and produces interesting results?
Hey, there's a seed for a hard sci-fi novel: we live in a simulation (or pocket universe), the laws of which were intelligently designed to produce aggressive life forms in order to make entertaining viewing for the builders and their clients. So all the wars we decry actually saved our universe by keeping it 'interesting'.
(I find it interesting that I'm willing to allow that evolution as we know it is just a quirk of our universe's dynamics, but I assume that commerce is universal...)
Re: To John Wheeler, the race to explain time was personal
#10Earlier quoted context omitted.
> that simulating quantum mechanics is so computationally expensive that it isn’t done unless we’re looking at it This is a common misconception. It's more difficult to simulate a quantum system than a classical system. To simulate a classic system you have to simulate one posible state. To simulate a quantum system you must simulate all possible path. This is the advantage of quantum computers. With the hardware for…
I'm by no means an expert, but how about using Pilot Wave Theory to do the simulation? As I understand, you wouldn't need to simulate an exponential number of states, you just simulate the pilot wave. See also (very accessible): https://www.quora.com/Why-dont-more-physicists-subscribe-to-...
You must simulate the value of the wave at every point of the universe, or at least a grid that has enough points to have the correct precision. It's even more work. Imagine simulating all the waves in all the ocean in the Earth, but worse because there are some nonlocality effects.
You can probably do some kind of smart representation of the wave, were you decompose it in some smart functional base of smooth waves. With a very optimized representation the calculations would be equivalent to the usual quantum mechanics calculations. With a not smart enough representation you would get something that needs more calculations.