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Rebuilding Quantum Theory From Simple Physical Principles

quantamagazine.org

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Re: Rebuilding Quantum Theory From Simple Physical Principles

#21

Post by SomeStupidPoint »

danbruc wrote: post #15
SomeStupidPoint wrote: post #12

Earlier quoted context omitted.

Could you support the premise you can make an undetectable simulation? That's a key proposition and you don't support it at all. I find the idea highly questionable.

Do you think a NPC in a game could figure out that he is just a character controlled by the game logic? Current games are obviously far away from having conscious NPCs but I neither see any fundamental problem with having NPCs controlled by artificial brains nor any obvious way how such a NPC could figure out that he lives within a game. Or what if, while you are asleep, someone essentially detaches your brain from y…

Yes, lots of ways:

For example, in Minecraft you can build a redstone interferometer to detect things about the computer you're executing on and over time the statistical behavior will detect the physics of the real system.

A character in Minecraft could build a cosmic ray detector, for instance.

So yes, absolutely -- my expectation is that any intelligent structure in a computational "bubble" will be able to detect that it's in a bubble managed by some outside system.

Is your argument entirely from lack of imagination in how it could be done?

Re: Rebuilding Quantum Theory From Simple Physical Principles

#22

Post by tbtowzhtow »

elorant wrote: post #16
danbruc wrote: post #6

Earlier quoted context omitted.

I have to disagree and I can not really understand what is so appealing about the simulation idea to many. It is an idea that will lead nowhere because you are unable to distinguish a real universe from a simulated one. In order to do this you would have to know what at least one of those scenarios looks like and then compare the universe you observe to what you know to be true about a real or simulated universe. It…

It is appealing for three reasons. 1) As computer engineers we understand it's doable. Give it a couple of centuries and our civilization could reach a computing capacity to simulate the entire observable universe 2) A lot of things just don't make sense. Like consciousness for example. We can't define it, and we don't even know it it's real. If you take consciousness out of the equation humans are just laborious sof…

What coincidences? I have mine, a lifetimes worth, but there isn’t a framework for saying whether my experiences are somehow special and contrived by a higher intelligence, part of a simulated universe or something else, or just a misunderstood manifestation of some not yet discovered physical law. As far as I know, science doesn’t offer a technique to quantify what we experience as coincidence (beyond the trivial prayer for health example) in any way that evidentially supports the existence of a higher intelligence or design. We’ve replaced superstitions systematically with science, and this trend seems unlikely to change, although a merger of sorts seems an inevitable destination.

Experience is often personal and difficult to express using known human communication techniques, much less quantify scientifically. Heck, we can’t even agree on whether there is a hard problem. These explorations for new approaches to quantum physics simply give hope for further understanding of reality that we may have already considered (simulation theory, for instance) or others we have not. Fun to speculate, though, in the meantime.

As an aside, maybe religious folks are right, maybe MWI is true and heaven and hell exist in the multiverse. What’s possible in the mind can overwhelm to the point of shutdown given the right set of perceptions, and coincidence can certainly drive a person to insanity (or enlightenment) if crafted carefully enough. You can claim aliens contacted you, or that you have perceptions and experiences giving blindingly in-your-face obvious (to you) indication of some kind of contrived, controlled or influenced reality, but you’d better have science to back it up.

Re: Rebuilding Quantum Theory From Simple Physical Principles

#23

Post by gilbetron »

danbruc wrote: post #6
dboreham wrote: post #2

Reading this I see for the first time why the notion that the universe is a simulation isn't so far fetched.

I have to disagree and I can not really understand what is so appealing about the simulation idea to many. It is an idea that will lead nowhere because you are unable to distinguish a real universe from a simulated one. In order to do this you would have to know what at least one of those scenarios looks like and then compare the universe you observe to what you know to be true about a real or simulated universe. It…

Why are you unable to distinguish it? It is not, a priori, impossible. It is entirely possible that there may be ways to determine if we are in a simulation, depending on how the simulation is done. No simulation is perfect, and it is theoretical feasible to find the imperfections.

Re: Rebuilding Quantum Theory From Simple Physical Principles

#24

Post by AgentME »

SomeStupidPoint wrote: post #21
danbruc wrote: post #15

Earlier quoted context omitted.

Do you think a NPC in a game could figure out that he is just a character controlled by the game logic? Current games are obviously far away from having conscious NPCs but I neither see any fundamental problem with having NPCs controlled by artificial brains nor any obvious way how such a NPC could figure out that he lives within a game. Or what if, while you are asleep, someone essentially detaches your brain from y…

Yes, lots of ways: For example, in Minecraft you can build a redstone interferometer to detect things about the computer you're executing on and over time the statistical behavior will detect the physics of the real system. A character in Minecraft could build a cosmic ray detector, for instance. So yes, absolutely -- my expectation is that any intelligent structure in a computational "bubble" will be able to detect…

>For example, in Minecraft you can build a redstone interferometer to detect things about the computer you're executing on and over time the statistical behavior will detect the physics of the real system.

Only because minecraft does a lot of things to save from doing extra work, like unloading chunks or skipping frames if it's under load. If you remove those optimizations (and add some error-correcting ram or a redundant process to double-check calculations to protect from cosmic-ray-induced errors), then it's easy to make a minecraft-like game that's deterministic across platforms and doesn't reveal details about whatever platform it's on.

Take something like Ethereum's blockchain: it's not possible for an executable turing-complete contract to know what type of computer it's executing on, because the VM is strictly specified, and if there were any flaws that accidentally revealed information from the environment, then every nearly every node in the Ethereum p2p swarm would get different results and the blockchain would fork ridiculously and practically halt as all nodes desynchronized from each other until people updated the software to fix that bug.

Re: Rebuilding Quantum Theory From Simple Physical Principles

#25

Post by breatheoften »

danbruc wrote: post #6
dboreham wrote: post #2

Reading this I see for the first time why the notion that the universe is a simulation isn't so far fetched.

I have to disagree and I can not really understand what is so appealing about the simulation idea to many. It is an idea that will lead nowhere because you are unable to distinguish a real universe from a simulated one. In order to do this you would have to know what at least one of those scenarios looks like and then compare the universe you observe to what you know to be true about a real or simulated universe. It…

Maybe its an acknowledgement of something about the nature of abstraction from observation. Perhaps the true universe is and always be a simulation error away from observation -- under such a hypothesis, science will be an eternal process of finding details in our understanding which are actually accidental results of the simulation capacity of our current understanding, then figuring out how to remove the flaw, and then peaking behind the next curtain ...

Re: Rebuilding Quantum Theory From Simple Physical Principles

#26

Post by SomeStupidPoint »

indubitable wrote: post #20
SomeStupidPoint wrote: post #12

Earlier quoted context omitted.

Could you support the premise you can make an undetectable simulation? That's a key proposition and you don't support it at all. I find the idea highly questionable.

Consider that your perception of reality is just that. What your brain tells you and what is really there are not necessarily the same thing. There was another excellent article on QuantaMagazine arguing that there's even an evolutionary imperative that would drive our brains to beneficially misrepresent reality: https://www.quantamagazine.org/the-evolutionary-argument-aga... That article is a bit of another very int…

A child you made deaf like that would still discover sound as the vibrations that distorted the lenses on the eye once detection got sensitive enough.

I dispute the very notion that it's possible to cut someone off from the basic nature of reality, because you must fundamentally have constructed the cage from that reality and thus their interaction with their cage will reveal its mechanics (and hence the mechanics of reality) to them.

You can only make it take more time by suppressing noise, but eventually the "errors" will carry accurate information inside. (And someone inside can accelerate this process by causing noise in certain manners.)

> lacking outside interference

Depending on your interpretation of quantum mechanics, this is either impossible (Bohmian; maybe all of them) or insufficient (Copenhagen, MWI) -- in either case, small "errors" will reveal information about the actual nature of reality.

Re: Rebuilding Quantum Theory From Simple Physical Principles

#27

Post by danbruc »

SomeStupidPoint wrote: post #21
danbruc wrote: post #15

Earlier quoted context omitted.

Do you think a NPC in a game could figure out that he is just a character controlled by the game logic? Current games are obviously far away from having conscious NPCs but I neither see any fundamental problem with having NPCs controlled by artificial brains nor any obvious way how such a NPC could figure out that he lives within a game. Or what if, while you are asleep, someone essentially detaches your brain from y…

Yes, lots of ways: For example, in Minecraft you can build a redstone interferometer to detect things about the computer you're executing on and over time the statistical behavior will detect the physics of the real system. A character in Minecraft could build a cosmic ray detector, for instance. So yes, absolutely -- my expectation is that any intelligent structure in a computational "bubble" will be able to detect…

Is a redstone interferometer an actually thing, a quick search didn't turn anything up? But even if you could detect influences from the outer reality within the game world, how would you decide between them being part of the game mechanics and them being shadows of the outer world given that you have no ground truth knowledge of what the game is supposed to be like?

Re: Rebuilding Quantum Theory From Simple Physical Principles

#28

Post by danbruc »

gilbetron wrote: post #23
danbruc wrote: post #6

Earlier quoted context omitted.

I have to disagree and I can not really understand what is so appealing about the simulation idea to many. It is an idea that will lead nowhere because you are unable to distinguish a real universe from a simulated one. In order to do this you would have to know what at least one of those scenarios looks like and then compare the universe you observe to what you know to be true about a real or simulated universe. It…

Why are you unable to distinguish it? It is not, a priori, impossible. It is entirely possible that there may be ways to determine if we are in a simulation, depending on how the simulation is done. No simulation is perfect, and it is theoretical feasible to find the imperfections.

To look for imperfections in a simulation requires knowing what the real thing actually looks like. If our universe is a simulation, where do you get the knowledge from what a real universe looks like?

Re: Rebuilding Quantum Theory From Simple Physical Principles

#29

Post by chr1 »

danbruc wrote: post #18
elorant wrote: post #16

Earlier quoted context omitted.

It is appealing for three reasons. 1) As computer engineers we understand it's doable. Give it a couple of centuries and our civilization could reach a computing capacity to simulate the entire observable universe 2) A lot of things just don't make sense. Like consciousness for example. We can't define it, and we don't even know it it's real. If you take consciousness out of the equation humans are just laborious sof…

As computer engineers we understand it's doable. Give it a couple of centuries and our civilization could reach a computing capacity to simulate the entire observable universe This seems at the very least questionable. Why do you think you can simulate the entire universe just using a tiny fraction of the resources of the universe? It seems to me that could only work if the universe were highly compressible and I don…

You don't need to simulate the entire universe, just the tiny bit where interesting things are happening (read surface of earth), places farther away can be simulated with much lower precision as long as they look plausible.

In that sense the universe is indeed highly compressible as it is mostly empty/uninteresting.

The question is how large computing device is needed to simulate a brain, and whether that device can be digital or analog. If the size of such device can be comparable to the size of human body, then we can create a useful simulation.

Re: Rebuilding Quantum Theory From Simple Physical Principles

#30

Post by chr1 »

danbruc wrote: post #28
gilbetron wrote: post #23

Earlier quoted context omitted.

Why are you unable to distinguish it? It is not, a priori, impossible. It is entirely possible that there may be ways to determine if we are in a simulation, depending on how the simulation is done. No simulation is perfect, and it is theoretical feasible to find the imperfections.

To look for imperfections in a simulation requires knowing what the real thing actually looks like. If our universe is a simulation, where do you get the knowledge from what a real universe looks like?

You can look for contradictions, inconsistencies or for macro scale phenomena not explainable by micro scale laws.
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