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Physicists found a new quantum paradox that casts doubt on a pillar of reality

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Re: Physicists found a new quantum paradox that casts doubt on a pillar of reality

#141

Post by GoblinSlayer »

devit wrote: post #16
bondarchuk wrote: post #6

The original Wigner's friend paradox: https://en.wikipedia.org/wiki/Wigner%27s_friend The paradox seems to rest on magical thinking about consciousness, and if one simply accepts that a conscious observer can be in a superposition like any other piece of matter, the paradox is resolved. And, from the article: For Wigner, this was an absurd conclusion. Instead, he believed that once the consciousness of an observer be…

It indeed seems so, i.e. that there is no paradox in the many-worlds and possibly other interpretations (as a non-expert in quantum physics). How did they manage to get the paper accepted in the (supposedly selective) Nature Physics journal though? Is there something we are missing?

Such experiments criticize copenhagen interpretation, so as long as CI is moving, criticism is solid.

Re: Physicists found a new quantum paradox that casts doubt on a pillar of reality

#142

Post by GoblinSlayer »

Thorentis wrote: post #129
incognition wrote: post #126

Earlier quoted context omitted.

QM is not hand wavy and gives precise results for many practical problems. Your theory is wrong as per one of the simplest quantum experiment - the single electron double slit problem.

The variation of the double split experiment that supposedly proves that observance "changes" the outcome, is only a thought experiment, and therefore can be flawed due to incorrect thinking. Obviously, the basic double slit experiment which shows the wave/particle duality of light is done in practice and therefore empirical.

And how wave/particle duality is possible without superposition?

Re: Physicists found a new quantum paradox that casts doubt on a pillar of reality

#143

Post by thu2111 »

dencodev wrote: post #113
Zenbit_UX wrote: post #98

Earlier quoted context omitted.

> That being said if it was demonstrated that un collapsed wave functions are somehow more efficient to calculate that would definitely give credence to the simulation hypothesis. Well said. I can certainly imagine a few functions that may prove to be more efficient at generating waves than fixed known positions + velocity for every subatomic particle in the universe. Here's the part that really takes us off the rail…

if we're a simulation i somewhat doubt whoever made our simulation is really worried about "resources" and "efficiency". Whatever real universe that may exist may not even follow our laws of physics. Maybe energy is actually unlimited and free in the "real world". Maybe matter can be made from nothing effortlessly.

Why would someone build a simulation of a world utterly unlike their own?

When we build simulations for ourselves, they're always attempting to approximate reality as closely as possible. The goal is to learn useful things about our own world or society and to try out many forking paths, in a simplified representation of reality.

If we're in a simulation it stands to reason that whoever is running it is somewhat human-like, and exists in a world that has basically the same physical laws ... or at least, similar enough that sociological and technological development would be the same. For instance, the speed of light barrier is pretty damn inconvenient for us but would be great at blocking an arbitrarily large population and state space explosion. And why are these magic physical constants so arbitrary anyway?

If we are in a simulation, and our simulators did want to limit their resource consumption, adding in a few physical laws that are never really a problem in daily life and which block us from colonising the galaxy would be a nice way to do it.

Re: Physicists found a new quantum paradox that casts doubt on a pillar of reality

#144

Post by tsimionescu »

08-15 wrote: post #137
tsimionescu wrote: post #80

Earlier quoted context omitted.

In fact, all statistical experiments, from clinical trials to observations of Bell's Inequality depend on the idea that there exists either free will or true randomness (and that we can base our decisions on that source of randomness). If neither exist, then there is no such thing as statistically independent events, and no way to make statistical observations (since that would imply that your choice of what to measu…

> either free will or true randomness Isn't unpredictability enough?

No, you need statistical independence of the measurement choice to the measured quantity. In superdeterminism, this is not possible.

Re: Physicists found a new quantum paradox that casts doubt on a pillar of reality

#145

Post by jfengel »

canjobear wrote: post #46
ahelwer wrote: post #24

Earlier quoted context omitted.

Many-worlds interpretation takes care of this. Anyway, how do you know your experience of the world cannot be superposed? Have you ever been in superposition? We make up stories to maintain consistent histories all the time.

> how do you know your experience of the world cannot be superposed? For your experience of the world to be superposed it would mean that you carry out a quantum experiment with two mutually exclusive outcomes |x> and |y> and you actually experience the superposed result |x>+|y>. This would be like opening the box in the Schroedinger's cat experiment and actually observing the cat to be |alive>+|dead>, instead of eit…

It's "possible", but not really possible. The larger the object is, the harder it is to maintain superposition. Even the slightest nudge will tend to push it all into one state or other. Seeing the superposition directly would be like standing twenty octillion strands of spaghetti on end.

So it's "possible" but would never happen in a trillion lifetimes of the universe. You can tell the difference between that and "impossible" by watching the quantum mechanics work for a few isolated particles, and observing what it means for them to fall out of superposition equilibrium. But in practical terms, it's equivalent to impossible.

Re: Physicists found a new quantum paradox that casts doubt on a pillar of reality

#146

Post by jlokier »

GoblinSlayer wrote: post #138
jlokier wrote: post #130

Earlier quoted context omitted.

It's only wrong because it's not really an explanation. At best, it's a weak one. Saying that an active model of self "is" what we experience as the consciousness we experience doesn't tell us why we have that experience. We can just as easily imagine a complex machine with an active self-model that isn't conscious, as one that is.[1] So an active self-model doesn't tell us about consciousness. This shows them to be…

Why hard problem is even here? Consciousness isn't magic, because chinese room in conscious, and it has nothing to do with quantum mechanics, because of paradoxes.

That still doesn't explain why I'm conscious, something that I have direct, first-hand experience of.

> Consciousness isn't magic, because chinese room in conscious

That doesn't explain anything.

Does that explain to the person experiencing consciousness why they are? No it doesn't.

It just says "something else is conscious so you are too". Which is not an explanation, it's circular.

Is it relevant if the Chinese room is conscious as well? Not really.

I am curious, though. Do you consider a system (such as a Chinese room) to be conscious if it's only implicit, by writing down the rules it should run, without actually performing any of the rules? What if it's so implicit that we don't even write down anything, we just refer to it by name, and assume we would create the rules if we needed to as the first steps in execution? Is it conscious when nothing happens at all, but it could happen? If yes, does that mean every possible thing that could occur is conscious even if it doesn't occur? Every physical possibility is conscious? The whole world of abstract mathematics is conscious? If the answer to any of those is no, where do you draw the line between conscious things (Chinese room) and not-conscious things?

Re: Physicists found a new quantum paradox that casts doubt on a pillar of reality

#147

Post by dencodev »

thu2111 wrote: post #143
dencodev wrote: post #113

Earlier quoted context omitted.

if we're a simulation i somewhat doubt whoever made our simulation is really worried about "resources" and "efficiency". Whatever real universe that may exist may not even follow our laws of physics. Maybe energy is actually unlimited and free in the "real world". Maybe matter can be made from nothing effortlessly.

Why would someone build a simulation of a world utterly unlike their own? When we build simulations for ourselves, they're always attempting to approximate reality as closely as possible. The goal is to learn useful things about our own world or society and to try out many forking paths, in a simplified representation of reality. If we're in a simulation it stands to reason that whoever is running it is somewhat huma…

Conversely, I would wonder why anyone would simulate something so similar to their own reality. We've already seen with humans that history repeats itself endlessly. Humans haven't really fundamentally changed in thousands of years. And humans do studies of the sociology of other species all the time. I think it'd be much more entertaining to simulate a world the laws are near opposite of our own. I would want to see what a species is capable of when restraints are lifted. To limit them to a single planet seems boring.

As an aside, I think one of my personal arguments that we're in a simulation is that we live in such an interesting time. We're beyond a world with 95% farmers. Technology is advancing faster than ever before. It's such a critical time in human history and the 20th century is personally where I'd choose to start a human simulation. It's convenient that this is our shared spot in time.

Re: Physicists found a new quantum paradox that casts doubt on a pillar of reality

#148

Post by tsimionescu »

elwell wrote: post #95
tsimionescu wrote: post #88

Earlier quoted context omitted.

They may or may not have perfect knowledge, but if they don't have free will or any ability to randomly choose participants, then there is no reason to trust that the patients they choose are not correlated to the medicine they are testing, such that all of the patients they chose will have the maximum response possible to the medicine, with the least amount of side effects.

> They may or may not have perfect knowledge At least as I was using the term, no one has perfect knowledge. > ability to randomly choose participants Here, pseudorandom is good enough, and I think all we have.

The whole premise of superdeterminism is that things which we deem to be uncorrelated are in fact correlated in such a way as to respect Bell inequalities while still preserving local realism.

The bell inequalities have been shown to hold true when the measuring 'decision' was left to signals coming from a pulsar some untold number of millions of light years away, implying that the particle you just generated today has its hidden state correlated with the state of that pulsar that many million years ago. So it seems that nature must be much more highly correlated that we would expect, so I don't know what you would trust as pseudo-random anymore.

Perhaps at some point we will be able to do the same triggered by fluctuations in the cosmic background radiation, proving that either quantum entanglement is not both local and real, or that the state of the two particles you just generated was decided at the big bang in such a way as to seem like the Bell inequalities are true.

Re: Physicists found a new quantum paradox that casts doubt on a pillar of reality

#149

Post by keymone »

jlokier wrote: post #130
keymone wrote: post #111

Earlier quoted context omitted.

Sure, just like a thermostat doesn’t experience the feeling of temperature, there is no need for human to feel it, so I understand that we need to explain why is it that we still feel the feeling rather than just observe the signal and react. So why is it wrong to explain this by the necessary recursiveness of predictive modeling that includes modeling “self”? We observe the temperature but we also observe ourselves…

It's only wrong because it's not really an explanation. At best, it's a weak one. Saying that an active model of self "is" what we experience as the consciousness we experience doesn't tell us why we have that experience. We can just as easily imagine a complex machine with an active self-model that isn't conscious, as one that is.[1] So an active self-model doesn't tell us about consciousness. This shows them to be…

lots of interesting replies, thanks. i'll aggregate my thoughts into single comment to keep this discussion more focused.

it seems to me the only rebuttal is "sure, self-models can exist but it's concievable that they can exist without an observer, so why is there an observer?" and to me it sounds similar to "sure, an eye can exist without abiogenesis, so why do we only find it in organisms that resulted from abiogenesis?"

an eye is just a collection of amino-acids, nothing prevents an eye from spontaneously assembling in a primordial soup and we recognize that's absolutely impossible. however i would posit that due to configuration of physical interactions in our universe, it's virtually guaranteed for an eye to develop in any life-form that is exposed to star's radiation in earth-like conditions.

similarly, just that we can think of p-zombie doesn't mean it's a simpler system to natually occure. we don't have understanding of building blocks of consciousness like we do with chemistry and biology but the answer to the why question seems to be quite simple: we observe ourselves because we evolved to. and we can find more and more primitive examples of self-observation in more and more primitive animals, so it's not some binary phenomena.

Re: Physicists found a new quantum paradox that casts doubt on a pillar of reality

#150

Post by keymone »

sooheon wrote: post #118
keymone wrote: post #111

Earlier quoted context omitted.

Sure, just like a thermostat doesn’t experience the feeling of temperature, there is no need for human to feel it, so I understand that we need to explain why is it that we still feel the feeling rather than just observe the signal and react. So why is it wrong to explain this by the necessary recursiveness of predictive modeling that includes modeling “self”? We observe the temperature but we also observe ourselves…

> So why is it wrong to explain this by the necessary recursiveness of predictive modeling that includes modeling “self”? It's not "wrong", it's just not parsimonious. A system can model itself without being conscious, any time you have state in a program you are doing this.

https://news.ycombinator.com/item?id=24336755
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