Either quantum state has to collapse at macroscopic level, or reality is unreal.
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Quantum reality is either weirdly different or it collapses
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So, does this, in connection with that experiment a couple years back where they reconstructed an image of a cat (cut out of cardboard) with a stream of photons that hadn't interacted with it, mean that FTL communication *is* possible?
Edit: I misremembered it as cut from silicon, but it looks like it's actually cardboard. I think this is the paper: https://www.nature.com/articles/nature13586
I know there was an Ars article about it, but I'm having trouble finding it.
Edit again: found it.
https://meincmagazine.com/science/2014/08 ... er-hit-it/
Edit: I misremembered it as cut from silicon, but it looks like it's actually cardboard. I think this is the paper: https://www.nature.com/articles/nature13586
I know there was an Ars article about it, but I'm having trouble finding it.
Edit again: found it.
https://meincmagazine.com/science/2014/08 ... er-hit-it/
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No, Faster that Light is prohibited in quantum mechanics by the so-called "no-cloning theorem": You cannot make a perfect copy of an unknown quantum state.
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No free will. Or, if that is too on the nose, free will is an illusion.
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Since everything we experience is an artifact of our brains, our measurements are not real. They are close enough to real that we are not extinct yet, but they are not real.
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People don't want to think they're actually automatons, they want to be special. Unless you mean objectively...in which case, I'm not aware of anything.
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But isn't this presuming causality and locality with regard to the source of their pain?
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I’m having difficulty with the idea of “collapse”, specifically that there is some boundary where things move from quantum to non-quantum. Why not move smoothly from quantum stuff to stuff that we don’t see much in the way of quantum effects from but doesn’t affect the “quantumness” of the same? As all their wave functions form interference patterns, once you involve a large amount of objects, it all looks the same to us at our present tech level, but underneath it’s still all quantum sh*t...? QFT and all that?
I’m sure a proper physicist will be along shortly to restore order (please?)
I’m sure a proper physicist will be along shortly to restore order (please?)
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Your set of possible conclusions is not complete.
Depending on your interpretation of the wave function, there might not be any issue at all. For instance, the many worlds interpretation accommodates Wigner's Friend quite easily. So does Quantum Bayesiansim. Many Worlds because of, well, the many worlds that each measurement created, and Quantum Bayesianism because when you think of the wave function in terms of Bayesian statistics rather than ensemble statistics, it describes the expectations of the observer about what will be measured rather than the thing being measured.
Under at least these two interpretations, this experiment is completely unproblematic. So one other possible conclusion is that this experiment has weeded out some of the interpretations of quantum mechanics as being inconsistent with measurement.
Depending on your interpretation of the wave function, there might not be any issue at all. For instance, the many worlds interpretation accommodates Wigner's Friend quite easily. So does Quantum Bayesiansim. Many Worlds because of, well, the many worlds that each measurement created, and Quantum Bayesianism because when you think of the wave function in terms of Bayesian statistics rather than ensemble statistics, it describes the expectations of the observer about what will be measured rather than the thing being measured.
Under at least these two interpretations, this experiment is completely unproblematic. So one other possible conclusion is that this experiment has weeded out some of the interpretations of quantum mechanics as being inconsistent with measurement.
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Because "quantumness" is sort of an all or nothing thing. There are superpositions or there are not. There is entanglement or there is not. There is decoherence or there is not.
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The problem with super-determinism objectively is that physics then becomes one big conspiracy theory: nature is organised in exactly such a way that it produces all these strange behaviours as explained in the article. Moreover, it does so in a way that reproduces the very elegant and economical theoretical predictions from quantum mechanics at the cost of exponentially complex underlying mechanisms. That's objectively ugly.
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That assumption is inherent to the Copenhagen interpretation. It is, in fact, one of the criticisms of this experiment. The observer is a photon, and a photon is not a classical observer.
Strictly speaking, though, that is not quite what an observer means. The Copenhagen interpretation describes the world as divided into quantum and classical realms, and collapse occurs when they interact. The classical realm imposes a unique outcome. Where that division occurs is left unspecified, and that is why among people who think about these things, Copenhagen is pretty much universally rejected. It involves a dose of metaphysics and retroactive justification.
Strictly speaking, though, that is not quite what an observer means. The Copenhagen interpretation describes the world as divided into quantum and classical realms, and collapse occurs when they interact. The classical realm imposes a unique outcome. Where that division occurs is left unspecified, and that is why among people who think about these things, Copenhagen is pretty much universally rejected. It involves a dose of metaphysics and retroactive justification.
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If all things are predetermined, nothing is your fault. I guess that's a convenient notion for some people.
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I'm a software engineer that never took a physics class, so forgive my ignorance. Is super-determinism uglier than the idea that intelligent beings are the exception to cause and effect? Or is that not the alternative to super-determinism?
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What's your source for saying "Copenhagen is pretty much universally rejected"?
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While trying to figure out what "local friendliness" is, as this articles description is confusing, I came across Scientific American's version of this article if you'd like another viewpoint: https://www.scientificamerican.com/arti ... um-theory/
I still have a hard time understanding what the big deal is with superpositions. Aren't they just us not measuring the rotation?
I still have a hard time understanding what the big deal is with superpositions. Aren't they just us not measuring the rotation?
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This is one of the same challenges in behavioral science. People don’t like it because it basically concludes with “free will is an illusion, behavior is probabilistically pre-determined.”
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Don't worry, you are superimposed in a quantum state and somewhere in an alternate universe, it does click. You can rest firm in that knowledge, or, rather, lack thereof.
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Isn't there already a precedent for believing quantum effect must some how transform or fizzle out or whatever at some macro level? I am thinking of, for example, the double slit experiment. Works great for photons. But push Alice through two slits and you end up with goo every time.
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Tss, where are the Friends of Wigner when you need them? Probably trying / having tried / will be trying to annoy the Qax again.
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So it could be a matter where you're in different regimes dominated by different rules?
In fluid mechanics, you can either have viscous-dominated flow (creeping flow), or inertia-dominated flow (inviscid or Eulerian flow) as limits. All flows have both inertia and viscosity so these are approximations, but they're good approximations outside of the overlap region. Perhaps when GR and QC are reconciled they will be found to be limits at two extremes of the quantum vs. classical approximations?
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I'm sure all this makes perfect sense. Just not to our feeble human minds.
Like trying to explain vision to a person born blind.
We can only measure what we can perceive or conceive of.
Like trying to explain vision to a person born blind.
We can only measure what we can perceive or conceive of.
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I don't understand one thing, how much impact is caused by the observer - photon ? Does the act of observing changes the state of observed state or not in this experiment ?
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So we truly are living on board the offshoot of Deep Thought, and our only purpose is to calculate the Ultimate Question?
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The problem with superdeterminism isn't really about free will-- it's that it eliminates the explanatory power of anything and everything! If only one arbitrary sequence of events is possible, cause and effect are meaningless. A golden dragon could pop up in the middle of time square and it would be no more inexplicable than anything else that happens.
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Real? What is real? If real is what you can feel, smell, taste and see, then 'real' is simply electrical signals interpreted by your brain. Do you think that's air you're breathing now?
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Didn't the ansible universe get around that by making FTL communication possible, but FTL travel was impossible for living beings?
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