Quantum physicists shed new light on relation between entanglement and nonlocality
January 30, 2012(PhysOrg.com) -- New research from the University of Bristol may disprove a long-standing conjecture made by one of the founders of quantum information science: that quantum states featuring positive partial transpose, a particular symmetry under time-reversal, can never lead to nonlocality.
When it comes to space and time, modern physics defies our intuition in the most dramatic way. Einstein's relativity theory tells us that time and space are intimately related and that absolute time is an illusion. Quantum mechanics, however, is at rest, and its predictions are perhaps even more astonishing than those of relativity.
In a nutshell, quantum theory tells us that two entangled particles behave as a single physical object, no matter how far apart they are. If a measurement is performed on one of these particles, the state of its distant twin is instantaneously modified.
This effect leads to quantum nonlocality, the fact that the correlation between results of local measurements performed on these particles are so strong, that they could not have been obtained from any pair of classical systems, such as two computers. To cut a long story short, it is as if quantum particles live outside space-time and experiments confirm this.
Understanding this phenomenon of quantum inseparability, arguably the most counter-intuitive feature of the theory, represents a major challenge of modern physics. A key point is that inseparability appears under various forms in quantum mechanics. Understanding precisely the relation between these various forms is a long-sought-after goal.
Writing in Physical Review Letters, Dr Tamas Vertesi from the Hungarian Academy of Sciences and Dr Nicolas Brunner from the University of Bristol make a significant step forward in this direction. They show that the weakest form of entanglement so-called undistillable entanglement can lead to quantum nonlocal correlations, the strongest form of inseparability in quantum mechanics. According to Professor Pawel Horodecki, a quantum theorist at the Gdansk University of Technology, entanglement is almost invisible in such systems, which makes it very surprising that they can exhibit nonlocality.
The work of Dr Vertesi and Dr Brunner also goes a long way towards disproving a long-standing conjecture made in 1999 by Professor Asher Peres, one of the founders of quantum information science.
Peres argued that quantum states featuring a particular symmetry under time-reversal known as partial transpose can never lead to nonlocality. All research in this area supported Peres conjecture until now. Vertesi and Brunners work proves, via a simple example, that the conjecture is false when three (or more) observers are present. It remains to be seen whether the conjecture could nevertheless hold true in the case of two observers.
Alongside its contribution to our understanding of the foundations of quantum theory, this work raises novel questions in quantum information science. In particular, it will spark a debate on the role that entanglement and nonlocality play in quantum information processing tasks, such as in quantum cryptography and computation.
More information: 'Quantum nonlocality does not imply entanglement distillability', by T. Vertesi and N. Brunner in Physical Review Letters 108, 030403 (2012). http://prl.aps.org … 8/i3/e030403
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Jan 30, 2012
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Because space, time, and causality are a-priori conceptual intuitions of the mind. They are not observable entities themselves, but are the form in which experience must take given evolved a-priori intellectual faculties of the mind. (how the mind operates on, and organizes sense experience).
An intuitive understanding of reality implies that reality was forced to conform within this subjective conceptual structure,.. this leads to inconsistencies as reality is misrepresented in this relatively arbitrary and artificial form (from macro to qm scale). The minds intuitive faculties simply don't function consistently on the qm level. This implies that the underlying reality (to qm) cannot ever be intuitively understood. Positivism prevails over realism.
[this post was made to annoy GhostOfOtto]
Jan 30, 2012
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At the water surface the observable objects are represented with solitons or wave packets, which can interact with both surface waves, both underwater waves. The mutual interaction with surface waves is easy to handle both mathematically, both experimentally, because just the surface waves are directly observable for us in the same way, like the transverse waves of light. But the mutual interaction trough longitudinal waves is something, which cannot be described with surface waves at all, so that only indeterministic, statistical approach of quantum mechanics has been developed here.
Nevertheless in context of dense aether model, these interactions are as real, as these observable ones.
Jan 30, 2012
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And I say that all depends on WHO is intuitively understanding. I suggest you read the work of David Deutsch before you say never.
I am lodging a formal complaint to the editors of PhysOrg for pulling Erik D.Andrulis' paper 'The Theory of the Origin, Evolution, and Nature of Life. It was pulled by Case Western and in an act of censorship, Physorg followed suit without a mention of its reasons for retraction. Andrulis' work is controversial but no more so than much of QM. I commented on the similarity to the reaction to Wilhelm Reich's books, which were burned in the 1950's by the F.D.A.! Overnight, the paper by Andrulis disappeared, making me realize you don't have to burn anyone's newly published ideas anymore, just the touch of a button will erase all traces of it. Shame on PhysOrg!
Jan 30, 2012
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Jan 30, 2012
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Not really, modern physics has a lot to learn about space and is still clueless about time.
Jan 30, 2012
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I will have to look into that. However, the many-worlds interpretation doesn't solve the measurement problem, and still requires a conscious observer to differentiate one possible world from another,.. but I'm not aware of his point.
Jan 30, 2012
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Here's a patent application from the "hippie" Erik D.Andrulis :
A method for preparing a cross-linked nucleic acid-protein complex; the method comprisingcontacting a cell with a stabilizer at a concentration and for a period of time effective for stabilizing protein-chromatin complexes, the concentration and the period of time being selected for specific stabilization of the interactions between chromatin proteins and chromatin; andisolating protein-chromatin complexes from the cell, the isolated protein-chromatin complexes forming the chromatome.
Now that we know Andrulis can run circles around you, encoded, consider making a retraction of your own.
Read more: http://www.faqs.o...kxYH7vh5
Jan 30, 2012
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Jan 30, 2012
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My point is, our perception of reality leads to what we consider "intuitive", but that perception of reality is not reality, so reality itself should not be expected to be intuitive.
I'm dubious that "time" is anything but a conceptual framework... our brain remembers things in order, and can imagine the future, and that gives us the impression of time. In reality the past and future do not exist, only the present.
Jan 30, 2012
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Jan 30, 2012
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Jan 31, 2012
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Yes unless it might be possible to understand uncertainty.
Uncertainty prevails over determinism.
Jan 31, 2012
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Jan 31, 2012
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Anyway, our entire human existance is representative of QM. A good analogy is - your wife when she goes menopausal. Her "inconsistancies" are something you have to deal with, too. Locality of a sort...
Jan 31, 2012
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Jan 31, 2012
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After all, I am a gyre (actually spelled geier)... Kind of a sideways shout out to Doc Andrulis. And, BTW - we're ALL gyres...
Jan 31, 2012
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Jan 31, 2012
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Jan 31, 2012
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Gravity cannot exceed the speed c, so "instantaneously" is the wrong word here. You're confusing static gravitational fields with gravitational waves. This is explained in the link below, paragraph 3 to 5.
http://en.wikiped..._gravity
Jan 31, 2012
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Hey nou whats with your great manifold of upraters?
Jan 31, 2012
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Jan 31, 2012
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Objectively, there is only information - no matter what stick you use to measure it...
Feb 04, 2012
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Do you know who Grigori ( George ) Yitshak (!saac )fallen from the House of David is ?
http://lunaticout...than-you
*bag over head*
Feb 06, 2012
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Feb 06, 2012
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The word "Propagation" indicates a sequential chain of events, a discripter of causality - ie.; - to change state upon the occurance of a previous event. Hence "simultaneous" does not apply.
Feb 06, 2012
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http://www.youtub...D0Ka6TsY
Feb 06, 2012
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