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To John Wheeler, the race to explain time was personal

nautil.us

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Re: To John Wheeler, the race to explain time was personal

#11

Post by dr_dshiv »

amelius wrote: post #8
gus_massa wrote: post #6

Earlier 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-...

I was wondering how this article would read from a Bohmian perspective. It would seem to be an alternative to creating the universe as a result of perceptions in the modern era. (Damn Copenhagen interpretation)

I was also wondering about entropy as the arrow of time -- positrons are just as subject to entropy, no?

Re: To John Wheeler, the race to explain time was personal

#12

Post by commentor10 »

empath75 wrote: post #2

On 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.

I find it funny how people are so ready to believe the universe must be computing the same way our models must. The universe simply exists - it's not necessary for it to adhere to our human perceptions - not be a long shot. There's a vast gulf between the model and the modeled. That our theories quickly become uncomputable says more about their unfitness than the universe's functioning. To say otherwise is to negate the fundamental autonomy of the universe. We should be humbled by the universe precisely because our best models to understand it quickly diverge to where our minds and tools may not.

Re: To John Wheeler, the race to explain time was personal

#13

Post by kgwgk »

amelius wrote: post #8
gus_massa wrote: post #6

Earlier 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-...

The equations are not simpler, there is no “just”.

Re: To John Wheeler, the race to explain time was personal

#14

Post by jerf »

ben_w wrote: post #7
bloak wrote: post #5

Earlier quoted context omitted.

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.

Another possibility is simply that they've got wildly more resources than we can imagine. It's ferociously expensive to run the universe on a classical simulation of QM, but finite. We have no particular reason to believe this "higher reality" doesn't have this level of resources. I've often pondered our universe as the moral equivalent of an elementary school demonstration; what if we're some metaphorical elementary kid's homework, because our physics is relatively simple (assuming some ToE that may actually be simpler than meets the current eye) and produces interesting results?

We can reasonably discuss the feasibility of simulating our universe using our universe. We can do some reasonable discussion of "universes that run something like ours but with some differences". We are profoundly ignorant about everything else.

Re: To John Wheeler, the race to explain time was personal

#15

Post by nixpulvis »

taneq wrote: post #9
bloak wrote: post #5

Earlier quoted context omitted.

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…

Watch South Park's "Canceled".

Re: To John Wheeler, the race to explain time was personal

#16

Post by nixpulvis »

jerf wrote: post #14
ben_w wrote: post #7

Earlier quoted context omitted.

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.

Another possibility is simply that they've got wildly more resources than we can imagine. It's ferociously expensive to run the universe on a classical simulation of QM, but finite. We have no particular reason to believe this "higher reality" doesn't have this level of resources. I've often pondered our universe as the moral equivalent of an elementary school demonstration; what if we're some metaphorical elementary…

I can't help but find it unsettling listening to a subject of the universe describe it as "relatively simple". Simple relative to what?! Some arbitrary more complex system? Well Sure!

Frankly, I don't think it's a question of complexity, or even expressivity, but more one of encapsulation and information hiding.

Re: To John Wheeler, the race to explain time was personal

#17

Post by mabbo »

empath75 wrote: post #2

On 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.

So you're saying the Universe is Lazy-Evaluated[0]?

[0]https://en.wikipedia.org/wiki/Lazy_evaluation

Re: To John Wheeler, the race to explain time was personal

#18

Post by whatshisface »

nixpulvis wrote: post #16
jerf wrote: post #14

Earlier quoted context omitted.

Another possibility is simply that they've got wildly more resources than we can imagine. It's ferociously expensive to run the universe on a classical simulation of QM, but finite. We have no particular reason to believe this "higher reality" doesn't have this level of resources. I've often pondered our universe as the moral equivalent of an elementary school demonstration; what if we're some metaphorical elementary…

I can't help but find it unsettling listening to a subject of the universe describe it as "relatively simple". Simple relative to what?! Some arbitrary more complex system? Well Sure! Frankly, I don't think it's a question of complexity, or even expressivity, but more one of encapsulation and information hiding.

The fundamental laws of the universe, at present, seem to be a whole lot simpler than many of the things that arise from them. That's as much of a statement in that direction as I think can be supported.

Re: To John Wheeler, the race to explain time was personal

#19

Post by meowface »

sidlls wrote: post #4
yodon wrote: post #3

I 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.

I wonder if any of these nut letters have ever yielded useful scientific discoveries or advances. I figure one or two must have, even if only by accident, or indirectly.
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