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Study Says Quantum Wavefunction Is a Real Physical Object

Soulskill posted more than 2 years ago | from the don't-trip-on-the-wavefunctions dept.

Science 373

cekerr writes with this excerpt from an article in Nature "The wavefunction is a real physical object after all, say researchers. ... the new paper, by a trio of physicists led by Matthew Pusey at Imperial College London, presents a theorem showing that if a quantum wavefunction were purely a statistical tool, then even quantum states that are unconnected across space and time would be able to communicate with each other. As that seems very unlikely to be true, the researchers conclude that the wavefunction must be physically real after all. David Wallace, a philosopher of physics at the University of Oxford, UK, says that the theorem is the most important result in the foundations of quantum mechanics that he has seen in his 15-year professional career. 'This strips away obscurity and shows you can't have an interpretation of a quantum state as probabilistic,' he says."

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Bring back US jobs! (-1, Offtopic)

Anonymous Coward | more than 2 years ago | (#38100826)

And this is exactly why we need SOPA. Innovation like this would not be possible anymore if we let rogue foreigners pirate our IP. Please help reelect such fine representatives such as the bill's introducer Lamar Smith (R) and true patriot co-sponsors such as Bob Goodlatte (R), Dennis R. Ross (R), Elton Gallegy (R), Marsha Blackburn (R), Mary Bono Mack (R), Steve Chabot (R), Timothy Griffin (R), Lee Terry (R), Mark Amodei (R), John Carter (R), Peter King (R), Thomas Marino (R), Alan Nunnelee (R), Steve Scalise (R). Bring back home the $135 billion bring stolen from this country by pirates and counterfeiters.

Re:Bring back US jobs! (5, Funny)

Skarecrow77 (1714214) | more than 2 years ago | (#38100940)

Yes yes... Some amazing American innovation done at the ... Imperial college of... London?

They mean London, Arkansas, right?

Re:Bring back US jobs! (-1, Flamebait)

Threni (635302) | more than 2 years ago | (#38101020)

Cheer up, fatty! This work was done in London. There's still plenty of doughnuts to go round.

Re:Bring back US jobs! (2)

Trubadidudei (1404187) | more than 2 years ago | (#38101404)

Ladies and gentlemen please look to the to the AC above. Observe the unrelated statements, the illogical statements, and the excessive long list of names being laid out for no particular reason, in a very non-slashdotesque manner.

Gentlemen, and ladies, we have ourselves an employee of the misinformation industry.

Re:Bring back US jobs! (-1, Offtopic)

RoccamOccam (953524) | more than 2 years ago | (#38101484)

As before, I'm sure that you didn't mean to leave all of the esteemed Democratic representatives that are co-sponsoring the bill: Rep. John Barrow [D, GA-12], Rep. Karen Bass [D, CA-33], Rep. Howard Berman [D, CA-28], Rep. John Conyers [D, MI-14], Rep. Ted Deutch [D, FL-19], Rep. Ben Luján [D, NM-3], Rep. William Owens [D, NY-23], Rep. Adam Schiff [D, CA-29], Rep. Debbie Wasserman Schultz [D, FL-20], Rep. Melvin Watt [D, NC-12]

Re:Bring back US jobs! (-1)

Anonymous Coward | more than 2 years ago | (#38101550)

Those are just traitors trying to hide themselves as patriots. Besides the dems make up less than half of the sponsors so they are insignificant (14 R to 10 D).

Oh man, University flashbacks (5, Funny)

Anonymous Coward | more than 2 years ago | (#38100840)

One of the stumbling blocks for learning this stuff at school was the people were hung up on the idea of "this-space", "that-space". It was a revelation to me that when they said "probability space" it was only a space in the mathematical sense (ie, something with N dimensions that could be graphed if N were not too large).

The way I saw it, people were prejudiced to believe that these were real spaces, the prejudice being that physics is strange at that level, thus there must be strange bizarre types of space. Nope. They were just things with N numerical characteristics.

Now you're telling me there really are strange spaces? That sucks.

Data vs Logic (4, Interesting)

VernonNemitz (581327) | more than 2 years ago | (#38101886)

The funniest thing is that this paper is coming out in the midst of the discussion of faster-than-light neutrinos. According to the interpretation presented in the article blurb at top, FTL neutrinos should be forbidden. If they actually exist, however, then that means that the quantum wave function really is a stastical thing and not a physical thing.

Sensible (4, Interesting)

exa (27197) | more than 2 years ago | (#38100854)

"Abstract objects" or "mathematical objects" don't exist in general, so this suggestion is rather plausible. Of course, the reality of the wave function had been proposed before, but new arguments are sorely needed in philosophy of quantum mechanics.

Re:Sensible (2, Interesting)

ackthpt (218170) | more than 2 years ago | (#38101308)

"Abstract objects" or "mathematical objects" don't exist in general, so this suggestion is rather plausible. Of course, the reality of the wave function had been proposed before, but new arguments are sorely needed in philosophy of quantum mechanics.

The most shocking realization is this: Quantum Mechanics are ceasing to be Crazy, they're Real and Definite.

It's like a part of my childhood just died.

Re:Sensible (4, Interesting)

exa (27197) | more than 2 years ago | (#38101668)

There have been several scientifically plausible interpretations. One thinks of MWI for instance.

It's just that some rather big names have unwittingly advocated superstitious, and completely nonsensical interpretations, the most famous of which are Copenhagen interpretation, Von Neumann Interpretation, and Penrose's assorted BS.

Except ... (5, Insightful)

tomhudson (43916) | more than 2 years ago | (#38101830)

As that seems very unlikely to be true, the researchers conclude that the wavefunction must be physically real

I could go back a couple of centuries and make the same flawed logical argument - "as it is unlikely that the earth moves, therefore it MUST be the center of the universe."

Re:Sensible (1)

Hatta (162192) | more than 2 years ago | (#38101572)

Of course they exist. They have properties. Something non-existant can't be said to have any properties besides non-existance.

Re:Sensible (1)

exa (27197) | more than 2 years ago | (#38101644)

Sure, I'm waiting for your empirical proof that "the empty set" exists. Write to me at exa@heavensucks.org

Re:Sensible (5, Funny)

thedonger (1317951) | more than 2 years ago | (#38101760)

My salt and pepper shakers came as a set. They did not, however, come with salt and pepper in them. They were a - wait for it - Empty Set.

Hope I didn't break the maths too much.

Re:Sensible (1, Insightful)

Hatta (162192) | more than 2 years ago | (#38102004)

The fact that you can do math with it is empirical proof that it exists. If it didn't, you couldn't do math with it.

Re:Sensible (1)

melikamp (631205) | more than 2 years ago | (#38102028)

In what sense do mathematical objects not exist? The physical sense? I am agnostic about that. Philosophically speaking, the world could turn out to be a giant continuous massively parallel computation, and then physics IS math, and nothing BUT mathematical objects exists. I can't think of any way to test for that. Although I have to admit, a non-math universe may seem more credible simply because we can't even begin to draw a mathematical theory of everything. All of the current theories seem to break down at some scales and/or energy levels, so may be we live in an ultimately chaotic universe with some statistical leanings.

Alternative... (0)

Anonymous Coward | more than 2 years ago | (#38100856)

Can someone explain to me why having a wave function as a real object is less ridiculous then the alternative?

Re:Alternative... (1)

blueg3 (192743) | more than 2 years ago | (#38100872)

It's not ridiculous at all, it's just counterintuitive. But then, intuition about such things is difficult at best.

Re:Alternative... (4, Interesting)

sexconker (1179573) | more than 2 years ago | (#38101134)

Because if the "wave function" is a real object, then there is no probabilistic nature to quantum shit - it just means we are currently unable to directly measure the "wave function" without "collapsing" it. If it's not probabilistic, all the fuzziness of quantum physics goes away. Schrodinger's cat is dead, Einstein was right when he said God doesn't play dice, entanglement is horse shit, everyone who works with string theory is a moron, etc.

Re:Alternative... (5, Funny)

akirchhoff (95640) | more than 2 years ago | (#38101514)

Sheldon Cooper is going to be pissed.....

Re:Alternative... (3, Insightful)

Lokitoth (1069508) | more than 2 years ago | (#38101754)

Not quite; the paper hinges on having in existence a lambda that is a complete physical state that is the superset of the various properties defined by the wavefunction. That seems, at first, like a hidden-variable theory, which would come back to your statement. However, all they are saying is that the statistical interpretation allows for a generator of a pure state may yield a physical state that can "collapse" into the other state.

I am not very happy with at least the first argument (have not worked my way through the second) since the initial assumption breaks the preparation, as I see it, because having lamba be compatible with either of two unequal, pure, non-orthagonal states implies that the only part of lambda that can yield independent measurements is the set of properties not in the intersection of |phi_0> and |phi_1>. That would seem to imply that lambda cannot be generated by either a generator of pure state |phi_0> or |phi_1>, unless I am missing something important.

Re:Alternative... (5, Insightful)

maxwell demon (590494) | more than 2 years ago | (#38101926)

Because if the "wave function" is a real object, then there is no probabilistic nature to quantum shit - it just means we are currently unable to directly measure the "wave function" without "collapsing" it. If it's not probabilistic, all the fuzziness of quantum physics goes away. Schrodinger's cat is dead, Einstein was right when he said God doesn't play dice, entanglement is horse shit, everyone who works with string theory is a moron, etc.

Wrong. (And yes, I am a physicist working in quantum information)

The canonical formalism contains the "collapse" of the wave function on observation, and this collapse is probabilistic. And there are interpretations of quantum mechanics with real wave function and real collapse (e.g. the Ghirardi–Rimini–Weber theory). Now there also exist deterministic interpretations of quantum mechanics which also include the wave function as real object (such as Bohmian mechanics). In other words, the wave function being real is completely independent of the question whether the world is fundamentally deterministic or not.

By the way, the paper does not really prove that the wave function is real. What it proves is that if you assume that there is something like a real state of the quantum system at all (and assuming quantum mechanics is actually right) then that real state must include the full wave function. There are some physicists who claim that quantum systems don't have physical states at all (an idea known as Quantum Bayesianism). That assumption is not refuted by this paper.

And entanglement is a property of wave functions, therefore if wave functions are real, then obviously entanglement is real.

This is great for QM and physics. (3, Interesting)

mbkennel (97636) | more than 2 years ago | (#38102218)

I think it's great.

I think the wave function is a physically real object(*), and the randomness is not intrinsic or magically special but comes from thermodynamics and chaos, and, yes, Einstein was right: Copenhagen is a nonsensical load of bollocks.

More specifically that dice are not actually random in an ineffable sense, but their practical use has a sufficiently high Kolmogorov-Sinai entropy rate (roughly average amount of chaos generated per time) that they're random enough. In other words, quantum mechanics is regular physics, not mystical Copenhagen mumbo jumbo. Copenhagen works for computation, but that's because it's a very useful approximation for experimentally relevant circumstances, just like Fermi's "Golden Rules". Einstein was right, at least about the problem. His proposed solutions weren't, but the experimental evidence wasn't available until after he died and obviously he would have changed his mind given new results, because he was a physicist foremost and not a mystical philosopher.

Entanglement and uncertainty principle are not horse shit, because the central mystery of QM, that everything is operating in a Hilbert space still remains.

(*) To me, physically real means "acts as a source term in gravitation". This pretty clearly distinguishes "electrons/protons/photons" from "set of all sets of sets" crap and is as useful as any other description I know. Of course we don't have quantum gravity working yet but when we do it's pretty likely something like the wavefunction will be in there.

Re:Alternative... (1)

V!NCENT (1105021) | more than 2 years ago | (#38101958)

Because then wave-particle duality are really just the same thing? I don't know much about this subject, but it seems that we have to rethink light rays... ?
We can measure light as both a wave and a particle. But they are both physical? So is the particle a dot which waves? Or springs back to a dot and out again to a wave?

Who knows...

Re:Alternative... (1)

ObsessiveMathsFreak (773371) | more than 2 years ago | (#38102228)

The alternative was to treat the wave function as a purely mathematical object, and to interpret it purely in that way.

The difficulty here is what happens when you measure the position/momentum of an object? Does the wave function "collapse" to a point? What happens after you measure? Does it become a wave function again? What?

If the quantum spectral representation or orbitals something real, or is it just a mathematical convention analogous to Fourier series, or decimal digits? Should we see an electron as something like 0.333333333... or 1/3? This study suggests that we should see the wavefunction as we see 1/3, and not as the collection of place value numerals which we see in 0.33333....

So, if I throw wavefunction equations at friends, (1)

BMOC (2478408) | more than 2 years ago | (#38100862)

is that assault?

Re:So, if I throw wavefunction equations at friend (2)

shoehornjob (1632387) | more than 2 years ago | (#38101168)

So, if I throw wavefunctions equations at friends is that assult?

No. They'll just give you a funny look and ask what kind of drugs you are on.

Does this mean (2)

bugs2squash (1132591) | more than 2 years ago | (#38100888)

That there is uncertainty in the amplitude of the wave function too ?

Proof by disbelieving .. (5, Insightful)

roguegramma (982660) | more than 2 years ago | (#38100910)

This is what they have proven:
If a quantum wavefunction is purely a statistical tool, then quantum states that are unconnected across space and time are able to communicate with each other.

The rest is speculation.

IMO one observer's wavefunction is the other observer's statistical tool, where an observer is any ensemble of particles.

By the way, the wikipedia article on Bell's inquality stated something similar years ago.

Re:Proof by disbelieving .. (5, Insightful)

blueg3 (192743) | more than 2 years ago | (#38100976)

If a quantum wavefunction is purely a statistical tool, then quantum states that are unconnected across space and time are able to communicate with each other.

Actually, what they've proven is that either the wavefunction is a real object and not a statistical tool or quantum states that are unconnected across space and time are able to communicate with each other.

This is fairly similar to, though not the same as, Bell's Theorem.

The rest is speculation.

The paper is actually quite clear on their claims. The speculation was added by others, but is a reasonable interpretation.

What's definitely speculation is your comment, which seems to have no real basis in quantum mechanics:

IMO one observer's wavefunction is the other observer's statistical tool

Re:Proof by disbelieving .. (5, Informative)

Anonymous Coward | more than 2 years ago | (#38101522)

The big difference from Bell's theorem is that in Bell's theorem, the quantum states are entangled. Here they are not, and the idea that un-entangled states would be able to communicate with one another is a bit more problematic than the idea that entangled states would be able to communicate with one another.

Re:Proof by disbelieving .. (3, Insightful)

Dr. Spork (142693) | more than 2 years ago | (#38101606)

Exactly. And that difference is very important. It's quite an understatement to say that information-passing between unentangled states is "a bit more problematic" than EPR-style instant communication.

Re:Proof by disbelieving .. (-1)

Anonymous Coward | more than 2 years ago | (#38101536)

In laymen's terms, what he is telling you is that you're stupid...

Re:Proof by disbelieving .. (1)

m50d (797211) | more than 2 years ago | (#38101626)

Actually, what they've proven is that either the wavefunction is a real object and not a statistical tool or quantum states that are unconnected across space and time are able to communicate with each other.

Um, that's exactly what the part you quoted said. Learn to logic.

Re:Proof by disbelieving .. (1)

EdIII (1114411) | more than 2 years ago | (#38101846)

Learn to logic

Okay Yoda.

Re:Proof by disbelieving .. (1)

BritneySP2 (870776) | more than 2 years ago | (#38101964)

Actually, what they've proven is that either... or...

According to the elementary math. logic, "A implies B" is the same as "not A or B".

Weird (5, Funny)

0123456 (636235) | more than 2 years ago | (#38100952)

I don't remember covering 'proof by claiming that something is unlikely' in my Physics degree.

Re:Weird (5, Funny)

blueg3 (192743) | more than 2 years ago | (#38101002)

Did they cover reading the paper instead of a media summary? Because it's a pretty important skill in science.

Re:Weird (4, Informative)

BitZtream (692029) | more than 2 years ago | (#38101126)

This isn't science, this is slashdot. Facts are out the door here.

Re:Weird (2, Insightful)

tgd (2822) | more than 2 years ago | (#38101220)

I blame the trend in the 90's of feeling it was unfair to the stupid children to point out they're stupid.

Now an entire generation thinks their beliefs are facts because their dimwit parents and teachers never pointed out to them that they were idiots.

Re:Weird (3, Insightful)

MozeeToby (1163751) | more than 2 years ago | (#38101142)

Sure you did, it's called Occam's Razor. Which is more likely: All the planets in the solar system travel around the sun in approximately elliptical orbits OR All the planets in the solar system orbit the Earth in a complex arrangement of circles within circles within circles? Now that being said, I'm not sure that you can arbitrarily say disconnected quantum states are likely than connected ones, but allowing them to communicate would seem to posit some communications medium that we have never seen evidence of, so if I had to choose I'd say they are unable to communicate.

And besides all that, as many people have already pointed out, the claims of 'proof' have been added by the media; the actual research just says it's one or the other making no judgement as to which.

Bad example (5, Insightful)

rjh (40933) | more than 2 years ago | (#38101498)

Copernican theory was picked up fairly quickly because it offered a simpler view of the cosmos. Astronomers bought into it largely because of its simplicity -- in effect, following Occam's Razor. It took until the early twentieth century for Einstein to say "you're all a bunch of doofuses: Ptolemaic theory is just as valid as Copernican, it all depends on your frame of reference." Thanks to relativity we now know beyond any shadow of a doubt that Ptolemaic epicycles are equally valid: they're just more complex. There is no privileged frame of reference. It is as true to say the Earth circles the Sun as it is to say the Sun circles the Earth -- it's just that the equations are neater in one frame of reference, not that they are correct. This bears repeating: according to special relativity, there are no privileged frames of reference.

Naively applying Occam's Razor to the question leads people to a false sense of certainty: they tend to think, "I've applied Occam's Razor, therefore I am likely choosing the better answer," without ever thinking, "did I formulate the question correctly in the first place?"

Don't get me wrong, I like Occam's Razor. But when people use Copernican-versus-Ptolemaic theories as an example of Occam's success, well... that tells me a quick lesson needs to be given on how Occam's Razor utterly fails in that case.

Re:Bad example (1, Insightful)

Anonymous Coward | more than 2 years ago | (#38101768)

Um. The earth is not an inertial frame of reference. The forces causing the earth to orbit the sun, and not vice versa can be observed directy.

Special Relativity does not state that all propositions are equally true. It simply elaborates the interesting consequences of the measured speed of light being the same in every frame of reference.

Re:Bad example (0)

Anonymous Coward | more than 2 years ago | (#38101800)

All well and good but I think you're letting some historical bias into this argument.
He's using Occam's Razor as the facts are now, not in 1600.

It's still sharp.

Re:Bad example (0)

Anonymous Coward | more than 2 years ago | (#38102104)

It took until the early twentieth century for Einstein to say "you're all a bunch of doofuses: Ptolemaic theory is just as valid as Copernican, it all depends on your frame of reference."

It took until the late ninetieth century for Poincaré to say "you're all a bunch of doofuses: Ptolemaic theory is just as valid as Copernican, it all depends on your frame of reference."

FTFY.

Re:Bad example (1)

Luyseyal (3154) | more than 2 years ago | (#38102154)

General principle of relativity [wikipedia.org]

Special relativity predicts that an observer in an inertial reference frame doesn't see objects they'd describe as moving faster than the speed of light. However, in the non-inertial reference frame of Earth, treating a spot on the Earth as a fixed point, the stars are observed to move in the sky, circling once about the Earth per day. Since the stars are light years away, this observation means that, in the non-inertial reference frame of the Earth, anybody who looks at the stars is seeing objects which appear, to them, to be moving faster than the speed of light.

Since non-inertial reference frames do not abide by the special principle of relativity, such situations are not self-contradictory.

My take is that it's better to pick the "most inertial" frame you have available. It is a heuristic like Occam's Razor but the upshot is the math is easier.

-l

Re:Weird (0)

Anonymous Coward | more than 2 years ago | (#38101568)

allowing them to communicate would seem to posit some communications medium that we have never seen evidence of

... except for quantum entanglement traces in bubble chambers?

Re:Weird (1)

LateArthurDent (1403947) | more than 2 years ago | (#38102126)

Sure you did, it's called Occam's Razor.

Occam's Razor doesn't say anything about correctness.

Which is more likely: All the planets in the solar system travel around the sun in approximately elliptical orbits OR All the planets in the solar system orbit the Earth in a complex arrangement of circles within circles within circles?

If they give the exact same predictions, both matching observations with the same accuracy and precision, then you take the easier to calculate one. And that is what Occam's Razor says, actually: that it makes no sense to use anything more complex than you have to. As for which one is "correct", if both give the same position to at all points to all the planets, that means they are equivalent.

And besides all that, as many people have already pointed out, the claims of 'proof' have been added by the media; the actual research just says it's one or the other making no judgement as to which.

Yep.

Re:Weird (4, Insightful)

Anonymous Coward | more than 2 years ago | (#38101676)

Then your physics degree is worthless.

One of the most basic principles of science, in fact I would say it's the single most important principle in science, is that nothing is ever completely proven. It's only probabilistically proven, meaning the chance of it being wrong is so small that you can basically rule out that possibility.

What is the concept of falsifiability, one of the key principles in the scientific method? You try everything you can to disprove your hypothesis. You get everyone else to try and disprove it. You hit it with everything you've got, and if it withstands the assault, then you can say it's proven. But it's only proven to be true under the conditions that you used to test it. In other words, no matter how hard you try, it still might not be true. It's only extremely unlikely not to be true.

Ironically, that's the greatest strength of science - that it's fallible. And it openly admits that fact. It rejoices when somebody tells it that it was wrong all along, because that means there's still more to discover. That's the driving force behind science. We test what we can, claim something is proven after the tests support it, but always leave open the possibility that we'll discover some new information that helps to refine or sometimes even replace the theory. The only "proof" of anything is the claim that it's a more likely explanation of your observations than any other possibility.

Granted, the claim that something is unlikely is not itself sufficient to disprove it, and perhaps that's what you meant, so maybe I'm being a little harsh. My point is simply that every "proof" is still just a claim. It just happens to be the claim most supported by the evidence.

physical phenomenon (2)

P-niiice (1703362) | more than 2 years ago | (#38100960)

Wasn't this hinted at by those oil-droplet-on-vibrating-medium experiments that partially reproduced the wave/particle duality?

Don't you... (1)

Wooky_linuxer (685371) | more than 2 years ago | (#38100972)

dare step on my wavefunction, mister! Or I'll have to send my engevectors at you!

Nothing unreal exists (0, Insightful)

WaffleMonster (969671) | more than 2 years ago | (#38100974)

Everything is physically real. Stored Information is physically real. Concluding something is physically real says nothing useful about what it is or its properties.

To quote spock "Nothing unreal exists"

Re:Nothing unreal exists (3, Insightful)

blueg3 (192743) | more than 2 years ago | (#38101086)

Nothing unreal exists

That's an uninteresting tautology.

Everything is physically real.

This, on the other hand, is not true. Plenty of things have no physical reality: like abstract concepts. There is no physical quantity of "good" or "evil", for example. There's not even a physical quantity of "red" (not counting the unrelated color charge from QED). There are physical properties that make things red, but "redness" is not by itself physical.

One class of things that is not physically real is probability distributions. They describe information we possess about a real quantities, but the distribution itself is not real. They're common in statistical mechanics as well.

Re:Nothing unreal exists (1, Insightful)

BitZtream (692029) | more than 2 years ago | (#38101178)

This, on the other hand, is not true. Plenty of things have no physical reality: like abstract concepts.

Nope, the concept is physical real. Its a collection of organized molecules stored in various places in the universe which we interpret into thoughts. Those thoughts are the results of chemical reactions in the brain ... all very real things.

Just because it isn't a specific object you can grab without killing yourself doesn't make it any less real. You're trying to define it out of existence, which is a logical impossibility. It exists because you define it, Ergo Cognito Sum. There is a physical item backing your existence just like there are physical objects backing abstract concepts. Those physical objects just also happen to be part of your mind.

Is your consciousness not real?

Re:Nothing unreal exists (3, Interesting)

blueg3 (192743) | more than 2 years ago | (#38101240)

An instance of considering an abstract concept -- which is what the collection of molecule is -- and the concept itself are different.

It's like people on Slashdot don't even know basic philosophy. I suppose that would explain why so many people thought The Matrix was interesting.

Re:Nothing unreal exists (3, Interesting)

skids (119237) | more than 2 years ago | (#38102076)

"Concepts" cannot exist at all without some form of persistence. The persistence relies on physical objects (though I won't limit that to "chemical reactions" nor "in the brain" as per the parent post).

If a civilization develops the concept of boolean algebra, and then that civilization is completely destroyed and all record of the concept of boolean algebra is lost, "boolean algebra" ceases to exist. If another civilization arises and redevelops a concept that is in all respects similar, it is still not the same concept.

One could pretend to be an "outside observer", and compare the two concepts and call them the same concept, but then you have violated to conditions -- you have kept a record of what the concept from the destroyed civilization was, and that record exists in some physical form in order to get it from timespace A to timespace B.

Now it is tempting to say that since concepts like boolean algebra are developed methodically with a set of indisputable rules from axioms that they are "real" without being physical, but that presupposes that even stating the axioms does not rely on physical phenomena.

In other words, "mathematics" is really a verb when you get right down to it.

Re:Nothing unreal exists (1)

Spiridios (2406474) | more than 2 years ago | (#38102214)

It's like people on Slashdot don't even know basic philosophy. I suppose that would explain why so many people thought The Matrix was interesting.

The Matrix had bullet time, Carrie-Anne Moss, and Kung-Fu fighting. I don't recall philosophy being much more than filler between those things.

Re:Nothing unreal exists (5, Insightful)

smelch (1988698) | more than 2 years ago | (#38101310)

Oh grow up. This kind of bullshit philosophy drives me nuts. Just because the idea is stored somewhere in a physical arrangement only makes that specific instance of the idea as pertains to a human being able to recall it real. It does not make the subject of the thought real, which is what we're talking about. Nobody is denying thoughts manifest in physical ways, but just because I can think about a unicorn doesn't make the unicorn itself physically real, just the thought of it is physically real. If you don't understand the difference, you think too highly of your own intelligence.

Re:Nothing unreal exists (2)

Klync (152475) | more than 2 years ago | (#38101346)

I think you fail to understand what the term "abstract" means. My mind's conception of a circle may have a physical manifestation in my brain, but my mind's conception of that circle is not the abstract circle.

Before you start quoting Descartes, perhaps you need to revisit your Plato [arpast.org] .

Re:Nothing unreal exists (0)

Anonymous Coward | more than 2 years ago | (#38101226)

What does it really mean for something to be physically real though? You only know what real is by contrasting it with something that you categorize as "unreal".

Re:Nothing unreal exists (0)

Anonymous Coward | more than 2 years ago | (#38101272)

Your mother is unreal.

Re:Nothing unreal exists (0)

Anonymous Coward | more than 2 years ago | (#38101918)

Everything is physically real.

Assumption that physicalism (materialism) is true. Please demonstrate. Start with consciousness and then move over to universals. But good luck untangling those two knots. Philosophers have been going at it for millenia and we still don't have a convincing argument on either one way or another (there is no consensus). Lest you think this is just philosophers, mathematicians and scientists haven't reached a consensus either. Thus the Platonism versus constructivism (discovery vs invention) schools of thought in math. And physicists are by no means agreed that everything is physical.

Try this one out for size: It from Bit (physicist John Wheeler). Which means that all physical stuff derives from information, which is the bedrock of reality. Now if that is true, then are bits (qubits) physically real?

David Wallace (0)

Jakeula (1427201) | more than 2 years ago | (#38100978)

So that's where he went after he left Dunder Mifflin. Impressive.

Re:David Wallace (1)

elrous0 (869638) | more than 2 years ago | (#38101602)

I always suspected he would end up working under Pusey.

implications for cats (1)

Anonymous Coward | more than 2 years ago | (#38100988)

Lolz.

And your brain is just a switching device for different states of reality. This sentence branches into a hydra of different endings, including this one (this one) (this other one) (this other one). Maybe everything you imagine is actually image from realities;

THis MaGiC MoMent.

Sorry for this freaky post-- this version of me can't help but do what it does.

Why is it that reading this feels like I'm (1)

future assassin (639396) | more than 2 years ago | (#38100992)

watching The Big Bang Theory?

Re:Why is it that reading this feels like I'm (4, Funny)

eddy the lip (20794) | more than 2 years ago | (#38101418)

Pandering, poorly written and not very funny?

Yeah right (0)

Anonymous Coward | more than 2 years ago | (#38100994)

Next you'll be saying that neutrinos travel faster than light.

Then what is its wave function? (1)

bazmail (764941) | more than 2 years ago | (#38101018)

now that's meta

Prince de Broglie... (2, Interesting)

theNAM666 (179776) | more than 2 years ago | (#38101048)

Yawn. Did these guys ever read Prince de Broglie?

http://galileo.phys.virginia.edu/classes/252/Bohr_to_Waves/Bohr_to_Waves.html [virginia.edu]

http://en.wikipedia.org/wiki/Louis_de_Broglie [wikipedia.org]

A particle is a wave is a particle-wave; all we can say about the universe, is what we can say about the universe; there's no such thing as a "real physical object."

Re:Prince de Broglie... (1)

tencatl (2509490) | more than 2 years ago | (#38101140)

Actually de Broglie would prefer to be called duke, since he was not from England. Also, I doubt any physicist do not know about de Broglie.

Re:Prince de Broglie... (1)

theNAM666 (179776) | more than 2 years ago | (#38101282)

"The Duke" is already taken. And yeah, I figured the "real object" stuff came from the mind of the journalist, not the mind of a physicist :).

Re:Prince de Broglie... (1)

Anonymous Coward | more than 2 years ago | (#38101182)

Yawn.

I can understand why you might find it boring when someone learns, for the first time, something you already knew.

Just remember that it was also old news the first time you learned it.

Re:Prince de Broglie... (0)

Anonymous Coward | more than 2 years ago | (#38101724)

So, there's nothing we can know that can't isn't known?
There's nothing we can see that isn't shown?
There's nowhere we can be that isn't where we're supposed to be?

That's easy!

Re:Prince de Broglie... (0)

Anonymous Coward | more than 2 years ago | (#38102158)

All you need is love.

Would bounce as reviewer (2)

mbone (558574) | more than 2 years ago | (#38101066)

I would bounce this paper as a reviewer. It appears to be a recasting of Bell's Theorem, but it doesn't reference ANY of that work.

Re:Would bounce as reviewer (0)

Anonymous Coward | more than 2 years ago | (#38101348)

I'm not an expert (I do quantum optics), but it sounds to me as though their lambda is something akin to a hidden variable in usual hidden variable theories. Could anyone with more knowledge than myself confirm this?

Dumb question (2)

bigsexyjoe (581721) | more than 2 years ago | (#38101084)

What's the difference? What is the difference between something being a "mathematical description of reality" and being real? I mean you can go back and forth between if numbers are real, etc. Have they discovered something "more real" than they previously thought?

Re:Dumb question (2)

sexconker (1179573) | more than 2 years ago | (#38101208)

What's the difference? What is the difference between something being a "mathematical description of reality" and being real? I mean you can go back and forth between if numbers are real, etc. Have they discovered something "more real" than they previously thought?

Math is the study of patterns.
Physics is the study of reality.

We use math to describe physics. Our current quantum math tells us what will happen. Our best quantum math is currently probabilistic. All our finest measurements can only give us a guess as to what will happen. The math describes what we see.
If the wave function is a result of a real, physical thing, we can potential learn more about the real, physical thing, and perhaps measure that, and get take that into account in our math, thus removing all the probabilities. All the quantum fuzziness could go away.

Re:Dumb question (4, Informative)

BitZtream (692029) | more than 2 years ago | (#38101300)

Its more like this mathematical construct we had to describe something we really didn't understand ... but let other mathematical constructs work out properly and achieve results that matched reality ... in fact appears to be the proper mathematical construct to define a portion of reality.

But thats what the summary says, not what the article says.

What the article says is more long the lines of:

Well, either this math is right or faster than light communications are possible. As far as we can tell, we see evidence that suggests faster than light communication is possible, so we conclude that we were probably right about this mathematical construct.

Considering that we have conflicting (and also unproven) reports of faster than light travel, we have two directly conflicting scientific theories on the table at the moment that can not possibly be right.

Or it could just mean that neutrinos are faster than light and the universal speed limit is actually neutrinos speed, not photon speed.

Truth be told, it all doesn't matter until we achieve the speed of bad news.

Re:Dumb question (1)

DollyTheSheep (576243) | more than 2 years ago | (#38101854)

not a physicist here, but i think it is a pretty big difference, whether you treat something as a real physical object, whose existence and relationship with everything else you can and must explore or simply as a mathematical convenience to label it as an object without really believing it is one for the sake of simplifying calculations.

i think this has happend with electro-magnetic fields.

Re:Dumb question (1)

kwikrick (755625) | more than 2 years ago | (#38102070)

It's a very good question.

I'm not a physicist, and I couldn't understand most of the paper, but what it seems to suggest is that a quantum state must be somehow represented or stored in a physical object. So the quantum state is not simply a statistical description of how particles interact, but is something 'real' that interacts with particles.

I would guess this physical object would take the form of a particle and also take the form of a wave, i.e. a wave-particle or whatever you call it, like many other physical objects.

Multiple universes (universii?) (1)

wisebabo (638845) | more than 2 years ago | (#38101092)

So does this support or refute the contention that reality is made up of a very very large number of universes constantly being created at each quantum step? Isn't that what the Copenhagen interpretation implied?

Re:Multiple universes (universii?) (1)

mbone (558574) | more than 2 years ago | (#38101248)

Probably neither, and that is a competing interpretation to the Copenhagen one.

Does this mean (1)

Nanosphere (1867972) | more than 2 years ago | (#38101096)

The universe is made from block transfer computations [wikia.com] ?

Re:Does this mean (0)

Anonymous Coward | more than 2 years ago | (#38101124)

No, but it's about as good an excuse as any for shoe-horning in a Doctor Who reference. Kudos.

CAPTCHA: puberty

careful with those "theorems" (0)

Anonymous Coward | more than 2 years ago | (#38101286)

You have to be really careful with those "theorems". There are hundreds of Physicists with nothing better to do than come up with some new "theorem". The journals are full of them. Problem is, a lot of these theorems are based on very shaky premises and shaky reasoning. Even the great Von Neumann laid a really big egg in this very same area-- his "proof" was demolished, but not before it skewed research in this area for decades.

horsepucky! (0)

Anonymous Coward | more than 2 years ago | (#38101336)

Whenever you require a probability function as part of a model, it means the model designer does not fully understand the process being modeled. However useful the model. Deal with it - we do not know everything yet.

The other option... (1)

smbell (974184) | more than 2 years ago | (#38101378)

I think the other possibility is just as fascinating, and possibly more impactful. The idea that all quantum states are related, even when not entangled. I'm certainly not a quantum physicist, but that seems like it would open amazing possibilities.

heh. quantum news. (1)

B3ryllium (571199) | more than 2 years ago | (#38101436)

Gotta love quantum news posts: meaningless and meaningful at the same time, like a newspaper written by Schroedinger's Cat.

Never been more appropriate (0)

Anonymous Coward | more than 2 years ago | (#38101466)

http://xkcd.com/849/

Lumo weighs in... (3, Informative)

Freddybear (1805256) | more than 2 years ago | (#38101598)

http://motls.blogspot.com/2011/11/nature-hypes-anti-qm-crackpot-paper-by.html [blogspot.com]

"Whatever way you choose to read the text [of the paper by Pusey et al], it makes no sense whatsoever. How they suddenly jump to the conclusion that there is a problem with the probabilistic meaning of the wave function remains completely mysterious."

This is garbage (1)

ocean_soul (1019086) | more than 2 years ago | (#38101630)

To every physicist it is immediately clear that this paper is complete nonsense. I don't want to waste time disproving it here and will simply refer you to this explanation.

Come on! Get a life. (1)

140Mandak262Jamuna (970587) | more than 2 years ago | (#38101632)

Wave function is a real object? You gotta be kidding. Next thing you will say "corporations are people". Oh! wait..

Help me out here (2)

He Who Waits (1102491) | more than 2 years ago | (#38101702)

So, what I'm not getting is this: If a waveform is a real physical object and not just a conceptual statistical function, what is the physical nature of this object? Is it a half-dead Schodinger's Cat? Or is it a world where the Cat lived superimposed on a world where it died? Is it (gulp) both?

Of course the wave function is real (1)

Anonymous Coward | more than 2 years ago | (#38101740)

The result of the wavefunction is a correlated outcome within everything embarked within it.

It should be obvious this behavior can not be explained by an abstract statstical statement as it would not include correlated outcomes.

I have no idea what if anything useful TFA is trying to say.

the new debate (5, Interesting)

Goldsmith (561202) | more than 2 years ago | (#38102042)

In the Nature blurb, there's a bit of discussion at the end that quantum states might all be linked, entangled or not.

In most physics classes, you learn quantum mechanics by calculating the interactions between isolated states. This thought process is natural and useful for certain areas of physics, but you end up worrying about hidden variables and how particles which are essentially in different universes can possibly communicate. This view does not need the wave function to be real, it can just be a statistical tool.

An alternative way of thinking about things is the idea that there are no isolated states (and no measurement apparatus which can exist outside the quantum system). From that point of view, one wave function is sufficient to describe the entire universe, traced back to the big bang. You don't need to worry about spooky action, everything obeys causality just fine assuming the wave function is real. There are some cosmological issues still, and it's not clear such a unified state is possible in an infinite universe.

At least we're starting to all agree wave functions are real and not just a statistical tool.

Its real, and .... (1)

PPH (736903) | more than 2 years ago | (#38102148)

... its a probability function. Its both!

Stand by to see which theory Schrodinger's cat buries in his litter box.

i for one (0)

Anonymous Coward | more than 2 years ago | (#38102178)

welcome our new theoretically physical quantum wavefunction-surfing overlords. time to crank up the Satriani.

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