Quantum Paradox Points To Shaky Foundations of Reality (sciencemag.org) 209
sciencehabit shares a report from Science Magazine: Nearly 60 years ago, the Nobel prize-winning physicist Eugene Wigner captured one of the many oddities of quantum mechanics in a thought experiment. He imagined a friend of his, sealed in a lab, measuring a particle such as an atom while Wigner stood outside. Quantum mechanics famously allows particles to occupy many locations at once -- a so-called superposition -- but the friend's observation "collapses" the particle to just one spot. Yet for Wigner, the superposition remains: The collapse occurs only when he makes a measurement sometime later. Worse, Wigner also sees the friend in a superposition. Their experiences directly conflict. Now, researchers in Australia and Taiwan offer perhaps the sharpest demonstration that Wigner's paradox is real. In a study published this week in Nature Physics, they transform the thought experiment into a mathematical theorem that confirms the irreconcilable contradiction at the heart of the scenario. The team also tests the theorem with an experiment, using photons as proxies for the humans. Whereas Wigner believed resolving the paradox requires quantum mechanics to break down for large systems such as human observers, some of the new study's authors believe something just as fundamental is on thin ice: objectivity. It could mean there is no such thing as an absolute fact, one that is as true for me as it is for you.
Multiverse (Score:5, Insightful)
some of the new study's authors believe something just as fundamental is on thin ice: objectivity. It could mean there is no such thing as an absolute fact, one that is as true for me as it is for you.
Occam's razor, which is more likely? The entire foundation of mathematics is on faulty ground, or we don't entirely understand quantum mechanics yet?
Re:Multiverse (Score:5, Insightful)
Remember that observers in this case refer to subatomic level particles, not humans. Humans have trillions of subatomic particles just in one neuron. The law of large numbers is in total control; or the law of incomprehensibly large numbers. Thought experiments are just that. You can't have the machinery that measures the decay of a single photon without it utterly influencing the photon in the first place.
The third options is that lay people cannot understand this, and try to oversimplify things so that they can grasp the concepts. They're still thinking about particles and waves, whereas the scientists deep into this are just thinking about the math and how whether it agrees with the observable evidence or not. Even the observing changes the math, the same way that an anthropologist will change the subjects being studied when he shows up in a helicopter to study a tribe that has had no contact with other humans before.
One can't say that truth is not objective based upon probability fields happening at a quantum level; you and I don't even see the same photons, so how can I even argue with you that you saw one decay or not? Our different views of reality only differ in infinitesimally small ways.
Re:Multiverse (Score:5, Interesting)
That's one of several interpretations of the math behind quantum mechanics. The one's I'm familiar with are:
1: The future causes the past as well as the past causing the future.
2: Superpredestinationism. Everything that is ever going to happen was implicit in the first state of the universe. Every energy state of every photon, much less every act of every human.
3: Everett-Graham-Wheeler multiverse.
4: Solipsism.
5: Wholeness and the implicate order. (I don't understand this one well enough to make a stab at what it means. See https://en.wikipedia.org/wiki/... [wikipedia.org]
These are broad categories, and I'm sure most of them have sub-categories. That they sound so different in English means that the math REALLY doesn't translate well, because they all reflect exactly the same math. Any claim that one is more probable than the other interpretations depends on something outside of current quantum physics.
My personal favorite is the 3: the EWG multiverse, but that's purely a matter of taste.
Do note, however, that one thing that isn't in ANY of these interpretations is "free will", or the importance of a human observer. It's just not there. The Wigner's friend paradox is catchy to people because it involves people, but the people aren't special to the theory. (Perhaps large objects are? Quantum decoherence postulates that. But it hasn't been proven, and Bose-Einstein condensates argue against that position.)
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Try Cramer's Transactional Interpretation. https://en.wikipedia.org/wiki/Transactional_interpretation [wikipedia.org]
Re:Multiverse (Score:4, Insightful)
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All those universes were born with the big bang.
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That'll make it even harder to fork.
Only if forking it requires net non-zero energy. Each fork could be accompanied by a corresponding anti-fork.
(I should be clear that I have no idea what I'm talking about. I do know that particle/anti-particle pairs randomly appear and then mutually annihilate all the time, so I'm just positing the same process at universe scale.)
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When you think of forking, it look monstrously impossible to do because you're looking at the problem incorrectly, IMHO.
If you start to think of fractals, and how small events are like Mandelbrot plots, the universe doesn't really fork with each new branch made, but instead the local fractal-fitting evolves.
This evolution, curve-fitting many dimensions, presumes that the context of a simple human experiment is empirical. Humans live in a pretty confined plane. Plentiful dimensions have been mathematically p
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That is an elegant way to fix the energy problem with the multiverses. But where does all the negative energy come from that is needed to cancel out all the energy of the mass that is in the universe?
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I can see how that could work, but it would require the starting position of the masses in the universe to initially be far away from each other in order to release energy as mass gets closer. That doesn't really match up with my intuition about big bang, but really nothing about that is intuitive.
My gut feeling is also that you have to bring stuff really close in order to cancel out the energy bound in mass. Given that G is small and c^2 is large.
Do you have any calculations/papers/books that describe how
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The wikipedia article is reasonably well referenced: https://en.wikipedia.org/wiki/... [wikipedia.org]
It's got a link to Guth's book where he talks about his proof that gravitational potential energy being the negative of the associated matter-bound energy: https://www.amazon.com/s?k=022... [amazon.com]
The zero point of gravitational potential energy is placed at infinite distance because this is also where the gravitational force equals zero. As two masses get closer, the force between them increases, as does their kinetic energy. To
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The Everett-Graham-Wheeler multiverse is nonsense. Think of how much energy it would take to fork the universe once.
Well it's just magic, so let's grant them that. (Is that's a BIIIIG Energizer Bunny in your pocket there, or are you happy to see me?)
I always here the multiverse described as branching a split "every time you flip a coin."
OH NOOOOOOOoooo, it's much more fun than that. Once again, it seems to imply somehow that "consciousness is special" -- and although I can't prove it, I don't think so. I believe the universe is "really there" and does things "even without us knowing about it". There might be un
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If everything that is ever going to happen was implicit in the first state of the universe, then is theoretically possible to know in advance of any event what the outcome of that event will be.
If it were, however, even theoretically possible to know in advance of any event what the outcome of that event was, then one should be able to, at least as a thought experiment, devise the concept of a perfect predictor that can accurately answer any yes or no question about the future correctly. However, what
Re:Multiverse (Score:5, Insightful)
Not if the universe is the most efficient possible computer for calculating the future of the universe.
And it might not be possible to know the initial state even if the future is deterministic. It might be possible to deduce the initial state only once time has played out to the very end.
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The mere existence of this question, a variation on the liar paradox, suggests that the future is intrinsically unknowable, even theoretically.
Does the barber paradox make barbers impossible?
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If everything that is ever going to happen was implicit in the first state of the universe, then is theoretically possible to know in advance of any event what the outcome of that event will be.
Let's make it a bit easier - it also means you can compute the past and know things, you haven't directly observed just from the state of the matter around you.
Incidentally - this exact thing is the premise of the "Devs" [imdb.com] series.
More generally, it suggests to me that non-determinism may be a emergent property of a certain types of otherwise entirely deterministic systems.
I feel it is the other way around - what we perceive as "determinism" is an emergent property of a system that is chaotic and non-deterministic at its core. It simply averages out one way or another at "large" scales.
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It may be only theoretically possible but not practically possible. Being able to track the state of every particle in the universe from the start and model the interactions from there sounds like its very computationally expensive. So expensive that it would require a computer larger than the universe its trying to model since overhead is a thing.
So you can still have a deterministic universe without the possibility of a predictor.
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You can also have a universe where the information necessary to make the prediction is not accessible to observation.
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"devise the concept of a perfect predictor that can accurately answer any yes or no question about the future correctly."
Hmm, think that is a variant of 42. Assuming you can have your predictor, then you have to ensure the question it is asked to be a question that can be answered by making use of knowledge of the future. Your question is not of that sort, therefore its not a valid question that the predictor can be expected to answer. Because your question is not ask-able you can't infer any meaning by the
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I am suggesting that if questions about a specific point in time which can be truthfully answered after an event cannot possibly be truthfully answered before the event, then it suggests that at least some information necessary to know what happens at that point in time cannot be used until that point. This is isomorphic to being non-deterministic, as it means that there are some future states that cannot possibly be accurately predicted before they occur.
One can also point out that both "yes" and "no"
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f everything that is ever going to happen was implicit in the first state of the universe, then is theoretically possible to know in advance of any event what the outcome of that event will be.
If it were, however, even theoretically possible to know in advance of any event what the outcome of that event was, then one should be able to, at least as a thought experiment, devise the concept of a perfect predictor that can accurately answer any yes or no question about the future correctly.
You've missed the core premise of quantum mechanics: there's a difference between what we observe, and a more fundamental reality represented by the wave equation.
The wave equation is entirely deterministic, and evolves over time in a simple, linear fashion. However, we have no access to it. It's not even theoretically possible to know the state if this fundamental reality with any sort of precision. Observation is non-deterministic, and it's limited in the information available. So, while there is a pe
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Do logical paradoxes invalidate the concept of logic? Your example sounds to me like just a case of garbage in, garbage out. Also, your predictor requires information that is unknown and possibly unknowable. There very well may be deterministic principles that govern every quantum event, but that doesn't mean that we can actually pull back the curtain. A quote from Terry Pratchett works pretty well here:
“God does not play dice with the universe; He plays an ineffable game of His own devising, which might be compared, from the perspective of any of the other players [i.e. everybody], to being involved in an obscure and complex variant of poker in a pitch-dark room, with blank cards, for infinite stakes, with a Dealer who won't tell you the rules, and who smiles all the time.”
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Really? The foundations of mathematics is on faulty ground? So you expect number theory to collapse upon itself? Peano arithmetic is somehow wrong. What were those algebraic topologists thinking? And don't get me started on category theory. The entire foundation of mathematics is threatened by an interpretation of quantum mechanics!!! Run for your lives!!!
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This is a directly related great read:
https://en.wikipedia.org/wiki/... [wikipedia.org]
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Well we've known that to be true since the one two punch of Russells paradox, and the Incompleteness theorem.
But that isn't *actually* what this article is about. The suggestion rather is that quantum indeterminism appears to have more macroscopic implications than originally envisioned.
I don't know what this "no objective reality" guff is about thought. That just seems to be some of the papers authors getting a bit excited to me. The statistical natu
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Or both.
a) Do you not understand Godel's incompleteness theorems [wikipedia.org]?
b) The fact that QM contradicts GR is proof that we don't understand either.
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Even if their interpretation is correct, it's not particularly surprising. Special relativity lets two observers disagree about when something happened. So quantum mechanics allows disagreement about where a particle is, or what path it took, and only when it's isolated from anything larger than another quantum particle? Throwing out objectivity might be a wee bit of hyperbole.
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Or that somehow this will get incorporated into common core math and that 1+1=3
Hey now, mathematical prescriptivism is classist. Stop that sarcasm, it's not appreciated.
Comment removed (Score:5, Funny)
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Re: Multiverse (Score:2, Funny)
Nah....bistromatics holds the prior art.
Just a problem for some interpretations (Score:5, Interesting)
This is just a problem for how we interpret the math, not a problem with the physics itself. In one way of looking at things, one person has become entangled with the system while another hasn't yet. It's not really a problem. The classical analog would be "my second measurement will be close to my first, but since you don't know what I measured, you just have to guess what you'll measure". Not a surprise.
This is a problem for the interpretation that the "collapse" is a real physical event, rather than simply a change in what one would predict for future observations. There's never been universal agreement about this, and it's not really scientific: no one thinks the collapse is itself observable. It's not a falsifiable hypothesis, it's a way of making sense of what the math is telling us.
There's a lot of trying to hang on to 100 year old ideas about reality that lingers on. People still talk about "wave or particle", but it's been 50 years since those ideas were anything more than handy abstractions. There are just fields. A particle is a useful way of referring to a persistent lump in a field, but you can't go too far with that way of thinking about things, it breaks down in all sorts of cases. When you drop the idea of particles with specific identities or locations, most of quantum mechanics stops seeming weird.
Re: Just a problem for some interpretations (Score:2)
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Re:Just a problem for some interpretations (Score:4, Funny)
Clearly, it has something to do with whether Alice has or hasn't given Bob her public key before noon.
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The person is not quantum entangled with the photon. The person may have one photon on their person that is quantum entangled with a different photon that is being "observed". This whole thought experiment boils down to
"imagine I was just a single photon", it's nonsensical and is not meant to be taking literally. Instead it's a way to try and describe what is happening at a subatomic level. Things can be highly spooky at that level but since trillions of trillions such spooky occurrences happen every tr
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Then the entire universe is entangled? Because your body doesn't have distinct borders so it interacts with everything around it, the planet under it's feet, the solar system, etc. A cascade starting with a single electron. "Observe" doesn't mean seeing, touching, smelling, noticing, etc, there is no "mind" here. Observe just means a single interaction at a subatomic level. If this observation takes place in your left little toe, and it also causes entanglement with electrons in your nose, then it will
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The present representative understanding of the quantum world is flawed because we still treat time as a constant flow.
The reality is that, at a quantum level, time is a seathing foam of disperate time domains.
Observations such as entanglement are not two separate sub-atomic particles acting in unison -- but a single particle which *appears* to be in two places at once due to the different time domains in which it simultaneously exists.
I had all this explained to me by a man wearing a tinfoil hat wilst I wa
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I was never happy with the concept of *collapse*, where you went quantum -> non-quantum at a defined point. AFAIK (and I am not going to pretend to have more than a basic understanding of the subject), the current explanation is that everything is always quantum but when dealing with large concentrations of states and/or complex interactions, the amount of interference going on means we can use classical means to determine outcome without too much uncertainty? It does not mean that things lose their *qua
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But whether we refer to them as particles or persistent lumps in a field, does the interpretatio
Erasure (Score:2)
Hawking's Black Hole Work (Score:5, Interesting)
Stephen Hawking's work on black holes essentially said that a black hole could emit ANYTHING.
The last work he did before his untimely passing was to show that it could emit anything at any distance from the center of mass of the hole.
Jerry Pournelle wrote it up. In private correspondence, I commented to Jerry that the work had the unmistakeable aroma of an indirect proof: Somewhere, we had a wrong assumption. Jerry told me he didn't disagree with me.
This seems to be more of the same. Something is fundamentally wrong, or incomplete, in our theoretical basis, and it is screaming at us "Wake up! Wake up!"
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Hawking radiation seems to be particle/anti-particle pairs. Nothing organized, so no planets will be popping out.
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Do you have link for that assertion? That would imply spontaneous virtual atom creation which wasn't part of any quantum vacuum I studied, and the Hawking radiation model we studied only had blackbody radiation emitted from virtual photon pair production.
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IIUC, spontaneous virtual atom creation is possible, but an EXTREMELY low probability event. You need to borrow a LOT of energy to make an atom. (And, of course, there are other complications that make it an even lower probability event than the mere energy requirement would imply.) I would guess that it hasn't happened even once in the history of the universe. (And, of course, you also need to emit the anti-atom at the same time.)
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I suppose the anti-atom (with negative mass) goes into the black hole just like the other photon in Hawking radiation (I never heard of such), but I have question if field theory even allows atom to be formed, there are ISSUES since constituents have to appear at EXACT SAME POINT in space, sure one electron and exactly one quark which then pulls two more into existence from quantum foam meaning you can't form the thing without the energy of 3 quarks and gluons, again all at the point where the electron is..
Re:Hawking's Black Hole Work (Score:5, Informative)
Jerry Pournelle wrote it up in "A Step Farther Out", his column in "Galaxy" at the time. It was later collected in the book by the same title. Dr. Robert Forward called Jerry and asked him if he'd like to attend a lecture by Dr. Hawking. Jerry reports not having to check his calendar before saying "yes", as nothing on his schedule was remotely as important. (In about 1995, I had exactly the same reaction when a co-worker asked me a similar question. Dr. Hawking was speaking at SMU.)
The key concepts are, first, that the region of space-time inside the black hole is 100% unobservable, and second, the exact position of the event horizon is not fixed.
It can move, and something that was inside can suddenly be outside. With the proper velocity vector, it may not be recaptured. There is no way to know what is in there, meaning there's no way to know what might come out.
Hawking later showed that the event horizon can jump a long distance, meaning that something can pop out at quite a distance. This later work, I don't recall where I saw it. It was some years ago, very shortly before Hawking's death, and Jerry passed away a few years back.
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Jerry just has a pop sci writer's knowledge of things though, his uni education was psychology and politics. He might have taking things to a romantic extreme being sci-fi writer looking for juicy angles in physics.. As a practical matter, anything getting to event horizon is going to be shredded for stellar mass black holes, for supermassive ones that spaghetti point is about 10% the way in BUT from our point of view that happens in infinitely far future. The event horizon can grow from our point of v
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This seems to be more of the same. Something is fundamentally wrong, or incomplete, in our theoretical basis, and it is screaming at us "Wake up! Wake up!"
The missing quantum gravity. Currently "known" physics is inconsistent. The only thing that is accurate are the observations. The currently used theory is fundamentally broken.
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Broken is too strong a word. "Incomplete" is the word you are looking for. QM has been experimentally verified to some stupidly small epsilon. Anyhow, we're really talking about QM's interpretation here.
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An inconsistent theory is fundamentally broken. That is theory crafting 101. An inconsistent theory can get anything and everything it predicts wrong. That is also a completely basic and fundamental thing.
Yes, I know the experimental validation is exceptionally strong. But we do know that the theory is not even a proper theory, because that requires consistency.
That also means that any interpretation of that fundamentally broken theory is completely meaningless, because it has no basis. It is just fantasizi
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The currently used theory is fundamentally broken.
I would say that it is incomplete, rather than broken. Semantics, I know, but it does matter.
Actually, it is fundamentally broken and that is not a matter of opinion, just of knowing the definitions. It predicts things that disagree with each other. That means it is not even a real theory, because that requires consistency.
Now, how small or large the fix will need to be (if it _can_ be fixed, the quantum and relativistic parts may be beyond saving), that remains to be seen. But before we can fix it, we need to find out what is actually going on in physical reality and that currently requires figuri
Thats why it has to be wrong. (Score:2)
This is not an endless recursion, it terminates with there is absolute reality.
A photon is not an observer (Score:2)
Re:A photon is not an observer (Score:5, Informative)
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A person does not observe a single photon in any meaningful way, anymore than my striking a match will affect the milky way. The math is about when the observer is also at a quantum level, when you try to scale the observer up to a person then you also need to scale the math up as well. And if you could scale the math up you would end up with something that looks almost the same as classical non-quantum physics.
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Not equivalent. A photon is an observer, but a special kind that can itself easily be in a superposition and so does not necessarily cause the system to decohere. A person, or even a typical "observer" like a sheet of polarizing film, can't do that.
Re:A photon is not an observer (Score:4, Insightful)
wrong, you've believed the oversimplified explanations. Any interaction with a system is an "observer", whether person or particle.
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That is not true. As I recall measurement involves scales large enough to cause decoherence , resulting in quasiclassical behaviour: statistics rather than quantum superposition.
Shaky foundations? (Score:2)
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No. The uncertainty principle is a fundamental element (arguably *the* fundamental element) of quantum theories. We have never, not once, made any observation that even hints it might be wrong. It's not just a physical principle either. It's a mathematical property of waves.
There is no paradox - explanation (Score:5, Insightful)
Yes, this means that my reality, which to me seems very well defined, is in fact in many different states to an observer I am hidden from. This is quantum mechanics.
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Cramer's Transactional Interpretation [wikipedia.org] solves the delayed choice paradox. In fact, it seems to address most of the weirdness of the Copenhagen Interpretation.
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Another way to look at it: This is essentially relativity for quantum mechanics.
Relativity removed the preferred observer status from space/time/velocity/acceleration. All observers will see physics working correctly from their own point of view, even though they don't necessarily see the same thing. It makes sense that quantum mechanics would have a similar idea - that each observer of a quantum system will see the physics working correctly from their own point of view, even though they don't necessarily
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And the issue that so many people have is that these sorts of thought experiments require elevation of consciousness to something that has mystical power.
There are interpretations other than Copenhagen that don't have this problem. Personally, I'm hoping they start to gain traction.
It's all about that box (Score:3)
I think the issue of whether this is possible in reality depends on the box. Let's call a box that can make this happen a Schrodinger box.
A Schrodinger box has to completely isolate its contents from observation. If you put a cat in the box and you can hear it meowing, you can hear glass breaking, or worse if the cat can claw through the box, it's not a Schrodinger box. If you can use an infrared camera to see through the box, it's not a Schrodinger box. If ambient magnetic fields can penetrate the box
Objectivity is not in jeopardy here (Score:2)
If Wigner and his friend are in communication, then Wigner himself is as entangled as his friend is with the system the friend was observing, and they will both agree on the same results of the observation. These findings don't put objectivity in any practical way that we usually mean it in jeopardy. Everyone will still agree about what the results of an experiment are, at least to the extent that they already do. It's just that if Wigner hasn't yet asked his friend what observation he made (or stronger tha
Re: Objectivity is not in jeopardy here (Score:2)
Stop clinging to your pseudo-science. Objectivity always was useless deluded wishful thinking nonsense. Especially since the human (or any neural) brain is literally not even able of it.
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But why should Wigner and his friend be the cause of the collapse? The janitor has yet to walk in the lab and observe their experiment.
"Cool experiment, Eugene. Do you want me to empty those trash cans now?"
Well no shit! (Score:2)
Did you get this just now?
You know it was considered established that reality is relative, for a looong time, right? At least since Einstein. But for philosophy, easily since the ancient Greeks.
Yes, the concept of an absolute reality, and absolute fact are nonsense, and the human brain is not even able of objectivity.
That doesn't mean chaos though.
You just can't say {event} anymore, but have to say {event(observer)}. It can still be one function for us all, if you define it right. But the sequence of events
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Reality is not relative. Your understanding of reality is relative. Our mathematical theories of reality are just that theories, they aren't the real thing...I guess the word "theory" gives it away. Get real.
Convenient (Score:2)
Oh it's common-day occurrence. (Score:2)
When you're waiting for a bus, the bus is in superposition of a multitude of quantum states along its route. The moment you light a cigarette, it collapses the superposition to a location just behind the corner.
And don't even start me on the orientation of USB ports. You must collapse both the plug and the socket quantum state separately, only then you'll be able to plug it in.
The universe is a simulation (Score:2)
The more we find out that the edges of reality are fuzzy, the more and more it seems likely that the universe is being simulated, with a finite degree of accuracy. All of these phenomenon are exactly what one would expect to occur in a simulation.
Overhyped click bait (Score:2)
Journalistic jumping to conclusions reminds of " sky is falling".
One explination. (Score:2)
The problem that presents is why do we see a consistent reality on the macro level. One simple, possible answer is that thier exists a signle observer of the whole universe.
Dewey Inconceivable Hypothesis (Score:2)
A news organization had a deadline and made a prediction based on data then available to it. The organization's proxy considered the prediction sufficiently likely that they made an editorial decision to proclaim Dewey as a fact. Another observer observed an incompatible likelihood. How was reality reconciled?
OK, Stupid Question (Score:2)
How does a person "see" their friend in a superposition? I thought that any interpretation of "seeing" would be an observation, which would in turn cause a collapse of said superposition.
(Apologies ahead of time if this was already covered in the article.)
Math is the wrong language here (Score:2)
Math describes what we see/observe. It's better than english for that. But when it conflicts with an observation, or when it doesn't make sense, it's just as incapable as any other language.
I'd have no problem, in this scenario as it's been described, with the outside observation collapsing the superposition to the same result. That the particle's position is set by observing it doesn't mandate that it hasn't already been set by a previous observation. It only mandates that the two "settings" have the sa
An overview of the realist/anti-realist schools .. (Score:3)
This is an overview [youtube.com] by a science writer on the anti-realist (Niels Bohr) and realist (Albert Einstein) schools of quantum mechanics. It is a lecture given to the Royal Institute.
a skewed view of physics (Score:4, Insightful)
I am a physicist, and went through all the standard quantum mechanics classes (and a few more besides) while getting my PhD, although quantum mechanics of any type is in no way my specialty!
It's really important to keep in mind that there are some unfortunate word choices used in quantum mechanics, specifically the use of the word "observer." This anthropomorphizes quantum states or incorrectly implies some role of consciousness in quantum mechanics. It would be much better if 120 years ago, physicists had starting this off using a root word like "interact" rather than "observe." There's pseudo-spiritual language in some early 20th century physics that is now a bit embarrassing.
The folks from TFA doing these measurements are purposefully separating a bit of the universe (in this case, some photons) from interactions with the rest of the universe. This is incredibly difficult to do, and not at all the "natural" state of anything you interact with day to day (though it may be the "natural" state of much of the universe). They do this to test somewhat esoteric areas of math-physics, not to understand reality as humans experience it. The stand-in of people for particles in this thought experiment (or any quantum mechanical thought experiment) is one of those embarrassing and misleading pseudo-spiritual elements of 20th century physics that somehow survived.
The Wigner's friend paradox is the idea that two people are quantum mechanically isolated from each other, then asking what happens when they interact. Who's version of "reality" is correct? This is not a situation that has ever happened (though such a situation could be engineered at great effort). The way the paradox is presented is pure fantasy; that being inside or outside a normal room is sufficient to create a quantum separation. If you boil this down to the simple physics, it's quite boring: you have a particle separated from the universe, and it interacts with a similarly isolated photon, thereby changing it's state (or not, depending on some quantum mechanical interaction). The separation from the universe is then broken and the state of the particle is revealed. When did the particle change it's state (or not)? When it interacted with the photon or when it re-joined the rest of the universe?
The areas of quantum mechanics that have been built to understand the world we interact with are (usually) not so strange and are rooted in how collections of particles interact with each other when NOT isolated. It's very common for people to take the "isolated particle" results and imagine what would happen if we lived on a planet that was made of a collection isolated particles rather than collections of rather closely and nearly continuously interacting particles.
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As long as you only make quantum wishes
Warning, your 'now' may vary (Score:2)
Not really news (Score:3)
The "Wigner's friend" thought experiment is nothing other than the Schrödinger's cat thought experiment, but with a human observing when an atom decays, rather than a cat being exposed to a vial of cyanide when an atom decays.
This is not news in any way. If you think quantum mechanics means that reality has "shaky foundations," it's no more and no less shaky than it was in the past. All of the usual interpretations of quantum mechanics are still the same usual interpretations of quantum mechanics.
The i
Trump had it right (Score:2, Funny)
Alternative facts are possible. Take that CNN
Re: (Score:2, Interesting)
I had much respect for CNN until late 2015/early 2016, as while biased it did not do outright falsehood. I did read it as my main/only source of world news (I'm in Poland). But during the 2016 US election campaign they quit the news business and became concerned only with: "does this piece benefit the lying {b,w}itch? Tout it even if untrue.".
I thus don't read any US-based news sources anymore (except Slashdot...) -- after CNN, pretty much anything in your country became either rabid left or rabid right,
Re: (Score:3)
Is there a significant difference. One is more cunning in their lying. I for one am sick and tired of this type of dishonesty. Oh what you didn't know that condition of the contract that we hid the 200 pages of legalese. 50% off everything (in tiny: exclusions apply), 99% fat free, its all sugar. No added sugar. Clinicaly tested (what was the result of that test) I for one am sick of having watch out for every possible way peoples words could screw me over. Society needs to stop accepting this type of dece
Re: Don't let Trump hear about this (Score:3, Funny)
Re: (Score:2)
I do agree with your comment on unnecessary Trump politics. However, I would also like to note that the entire legal system is based in a fundamental way on the idea of determining whap happened, objectively. Undermining objective reality might very well cause all kinds of philosophical legal issues.
Re: Don't let Trump hear about this (Score:2)
Isn't that already possible?
'I didn't murder the victim, I had my eyes closed. His wife killed him by observing the body'
Re: (Score:2)
That can't be right, it was $9.98 when I tried to see it.
Re: (Score:2)
Hmmmm....I like where you are going! The whole reality/universe is a mathematical system. The whole reality universe is a hologram. The whole reality universe is a not real. Wow!! Anyone can get in on this game. You've discovered a universal explanation system of mythic proportions. Have you told anyone else about this or are we to keep it secret?