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Quantum superposition now clocked at as long as a second

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From Phys.org:

Physicists have implemented the first experimental demonstration of everlasting quantum coherence—the phenomenon that occurs when a quantum system exists in a superposition of two or more states at once. Typically, quantum coherence lasts for only a fraction of a second before decoherence destroys the effect due to interactions between the quantum system and its surrounding environment.

The collaboration of physicists, led by Gerardo Adesso at The University of Nottingham and with members from the UK, Brazil, Italy, and Germany, have published a paper on the demonstration of the extreme resilience of quantum coherence in a recent issue of Physical Review Letters.

“Quantum properties can be exploited for disruptive technologies but are typically very fragile,” Adesso told Phys.org. “Here we report an experiment which shows for the first time that quantum coherence in a large ensemble of nuclear spins can be naturally preserved (‘frozen’) under exposure to strong dephasing noise at room temperature, without external control, and for timescales as long as a second and beyond.”

That may help provide an underpinning to human brain states (changing one’s mind in a second).

The researchers predict that the surprising effect can occur in larger systems composed of any even number of qubits. Odd-numbered qubit systems do not exhibit the resilience because the specific initial conditions supporting the phenomenon cannot be met due to the different geometry of quantum states in such instances.

The researchers also showed that the mechanism appears to be universal, since it does not depend on the specific measure used to quantify the amount of coherence. The researchers expect that this trait will make the mechanism especially useful for future applications. More.

See also: Central galaxy black hole a quantum computer?

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4 Replies to “Quantum superposition now clocked at as long as a second

  1. 1
    bornagain77 says:

    The ‘trick’ is described here:

    Forever quantum: physicists demonstrate everlasting quantum coherence – October 14, 2016 by Lisa Zyga
    Excerpt: “The trick lies in the fact that local decoherence acts in a preferred direction, which is perpendicular to the one in which coherence is measured,” Adesso explained. “Consequently, the resulting quantum states are overall degraded by such noise, but their observed coherence remains unaffected during the dynamics if the initial conditions are suitably chosen.”
    http://phys.org/news/2016-10-q.....rence.html

    ‘Suitably chosen’ being the key phrase. In other words, ‘suitably chosen’ means to intelligent design the initial conditions in such a way so as to maintain coherence in spite of noise.

    This should be a major step forward for the entire field quantum computation since overcoming noise in order to maintain coherence has been the number 1 obstacle preventing researchers from making any major advances in quantum computation.

    Quantum Computation problems 2010
    Excerpt:
    Interference – During the computation phase of a quantum calculation, the slightest disturbance in a quantum system (say a stray photon or wave of EM radiation) causes the quantum computation to collapse, a process known as decoherence. A quantum computer must be totally isolated from all external interference during the computation phase. Some success has been achieved with the use of qubits in intense magnetic fields, with the use of ions.
    http://whatis.techtarget.com/d.....-computing

    Quantum computing
    Excerpt: One of the greatest challenges is controlling or removing quantum decoherence. This usually means isolating the system from its environment as interactions with the external world cause the system to decohere. However, other sources of decoherence also exist. Examples include the quantum gates, and the lattice vibrations and background thermonuclear spin of the physical system used to implement the qubits. Decoherence is irreversible, as it is non-unitary, and is usually something that should be highly controlled, if not avoided.
    https://en.wikipedia.org/wiki/Quantum_computing#Quantum_decoherence

    And while this breakthrough represents a major advance for researchers being able to intelligently design quantum computers that maintain robust coherence in spite of noise, it should be noted that, once again, life has been utilizing the principles of quantum computation all along.

    In laying this out, first it is important to note that proteins do not find their final folded form by random search as would be expected in a neo-Darwinian view of things:

    The Humpty-Dumpty Effect: A Revolutionary Paper with Far-Reaching Implications – Paul Nelson – October 23, 2012
    Excerpt: Anyone who has studied the protein folding problem will have met the famous Levinthal paradox, formulated in 1969 by the molecular biologist Cyrus Levinthal. Put simply, the Levinthal paradox states that when one calculates the number of possible topological (rotational) configurations for the amino acids in even a small (say, 100 residue) unfolded protein, random search could never find the final folded conformation of that same protein during the lifetime of the physical universe. Therefore, concluded Levinthal, given that proteins obviously do fold, they are doing so, not by random search, but by following favored pathways. The challenge of the protein folding problem is to learn what those pathways are.
    http://www.evolutionnews.org/2.....65521.html

    Rubik’s Cube Is a Hand-Sized Illustration of Intelligent Design – Dec. 2, 2014
    Excerpt: The world record (for solving a Rubik’s cube) is now 4.904 seconds,,,
    You need a search algorithm (for solving a Rubik’s cube).,,,
    (Randomly) Trying all 43 x 10^18 (43 quintillion) combinations (of a Rubik’s cube) at 1 per second would take 1.3 trillion years. The robot would have a 50-50 chance of getting the solution in half that time, but it would already vastly exceed the time available (about forty times the age of the universe).,,,
    How fast can an intelligent cause solve it? 4.904 seconds. That’s the power of intelligent causes over unguided causes.,,,
    The Rubik’s cube is simple compared to a protein. Imagine solving a cube with 20 colors and 100 sides. Then imagine solving hundreds of different such cubes, each with its own solution, simultaneously in the same place at the same time (in nanoseconds). (That is exactly what is happening in each of the trillions of cells of your body as you read this right now).
    http://www.evolutionnews.org/2.....01311.html

    Confronting Science’s Logical Limits – John L. Casti – 1996
    Excerpt: It has been estimated that a supercomputer applying plausible rules for protein folding would need 10^127 years to find the final folded form for even a very short sequence consisting of just 100 amino acids. (The universe is 13.7 x 10^9 years old). In fact, in 1993 Aviezri S. Fraenkel of the University of Pennsylvania showed that the mathematical formulation of the protein-folding problem is computationally “hard” in the same way that the traveling-salesman problem is hard.
    http://www.cs.virginia.edu/~ro.....Limits.pdf

    As to “protein-folding problem is computationally “hard” in the same way that the traveling-salesman problem is hard”, it should also be noted that the traveling-salesman problem is ‘just about the meanest problems you can set a computer on’.

    DNA computer helps traveling salesman – Philip Ball – 2000
    Excerpt: Just about the meanest problems you can set a computer (on) belong to the class called ‘NP-complete’. The number of possible answers to these conundrums, and so the time required to find the correct solution, increases exponentially as the problem is scaled up in size. A famous example is the ‘travelling salesman’ puzzle, which involves finding the shortest route connecting all of a certain number of cities.,,,
    Solving the traveling-salesman problem is a little like finding the most stable folded shape of a protein’s chain-like molecular structure — in which the number of ‘cities’ can run to hundreds or even thousands.
    http://www.nature.com/news/200.....13-10.html

    And protein folding is indeed found to be a ‘NP-complete’ problem

    Combinatorial Algorithms for Protein Folding in Lattice
    Models: A Survey of Mathematical Results – 2009
    Excerpt: Protein Folding: Computational Complexity
    4.1
    NP-completeness: from 10^300 to 2 Amino Acid Types
    4.2
    NP-completeness: Protein Folding in Ad-Hoc Models
    4.3
    NP-completeness: Protein Folding in the HP-Model
    http://www.cs.brown.edu/~sorin.....survey.pdf

  2. 2
    bornagain77 says:

    Yet it is exactly this type of ‘traveling salesman problem’, i.e. NP complete problem, that quantum computers excel at:

    Speed Test of Quantum Versus Conventional Computing: Quantum Computer Wins – May 8, 2013
    Excerpt: quantum computing is, “in some cases, really, really fast.”
    McGeoch says the calculations the D-Wave excels at involve a specific combinatorial optimization problem, comparable in difficulty to the more famous “travelling salesperson” problem that’s been a foundation of theoretical computing for decades.,,,
    “This type of computer is not intended for surfing the internet, but it does solve this narrow but important type of problem really, really fast,” McGeoch says. “There are degrees of what it can do. If you want it to solve the exact problem it’s built to solve, at the problem sizes I tested, it’s thousands of times faster than anything I’m aware of. If you want it to solve more general problems of that size, I would say it competes — it does as well as some of the best things I’ve looked at. At this point it’s merely above average but shows a promising scaling trajectory.”
    per Science Daily

    Scientists achieve critical steps to building first practical quantum computer – April 30, 2015
    Excerpt: If a quantum computer could be built with just 50 quantum bits (qubits), no combination of today’s TOP500 supercomputers could successfully outperform it (for certain tasks).
    http://phys.org/news/2015-04-s.....antum.html

    That proteins have the inherent ability to perform quantum computation, and thus provide an adequate solution to the protein folding enigma, is established by the fact that proteins are now found to have quantum information embedded within them:

    Classical and Quantum Information Channels in Protein Chain – Dj. Koruga, A. Tomi?, Z. Ratkaj, L. Matija – 2006
    Abstract: Investigation of the properties of peptide plane in protein chain from both classical and quantum approach is presented. We calculated interatomic force constants for peptide plane and hydrogen bonds between peptide planes in protein chain. On the basis of force constants, displacements of each atom in peptide plane, and time of action we found that the value of the peptide plane action is close to the Planck constant. This indicates that peptide plane from the energy viewpoint possesses synergetic classical/quantum properties. Consideration of peptide planes in protein chain from information viewpoint also shows that protein chain possesses classical and quantum properties. So, it appears that protein chain behaves as a triple dual system: (1) structural – amino acids and peptide planes, (2) energy – classical and quantum state, and (3) information – classical and quantum coding. Based on experimental facts of protein chain, we proposed from the structure-energy-information viewpoint its synergetic code system.
    http://www.scientific.net/MSF.518.491

    Moreover, protein folding is now found to belong to the world of quantum physics and not to the world of classical physics as is presupposed in the reductive materialism which undergirds neo-Darwinian thought:

    Physicists Discover Quantum Law of Protein Folding – February 22, 2011
    Quantum mechanics finally explains why protein folding depends on temperature in such a strange way.
    Excerpt: First, a little background on protein folding. Proteins are long chains of amino acids that become biologically active only when they fold into specific, highly complex shapes. The puzzle is how proteins do this so quickly when they have so many possible configurations to choose from.
    To put this in perspective, a relatively small protein of only 100 amino acids can take some 10^100 different configurations. If it tried these shapes at the rate of 100 billion a second, it would take longer than the age of the universe to find the correct one. Just how these molecules do the job in nanoseconds, nobody knows.,,,
    Today, Luo and Lo say these curves can be easily explained if the process of folding is a quantum affair. By conventional thinking, a chain of amino acids can only change from one shape to another by mechanically passing though various shapes in between.
    But Luo and Lo say that if this process were a quantum one, the shape could change by quantum transition, meaning that the protein could ‘jump’ from one shape to another without necessarily forming the shapes in between.,,,
    Their astonishing result is that this quantum transition model fits the folding curves of 15 different proteins and even explains the difference in folding and unfolding rates of the same proteins.
    That’s a significant breakthrough. Luo and Lo’s equations amount to the first universal laws of protein folding. That’s the equivalent in biology to something like the thermodynamic laws in physics.
    http://www.technologyreview.co.....f-protein/

    This obviously far outclasses anything man has designed in his attempts at quantum computation thus far.

    Which brings us back to this quote from the article in the OP:

    but their observed coherence remains unaffected during the dynamics if the initial conditions are suitably chosen.”

    And again “suitably chosen” is the key term there. In other words an Intelligent Agent is required to choose the initial conditions in such a way so that the problem of noise can be overcome. And indeed, life appears to be set up in such a way so as to not only resist noise but to even utilize noise in such a way so as to maintain coherence.

    Quantum entanglement in hot systems – 2011
    Excerpt: The authors remark that this reverses the previous orthodoxy, which held that quantum effects could not exist in biological systems because of the amount of noise in these systems.,,, Environmental noise here drives a persistent and cyclic generation of new entanglement.,,, In summary, the authors say that they have demonstrated that entanglement can recur even in a hot noisy environment. In biological systems this can be related to changes in the conformation of macromolecules.
    http://quantum-mind.co.uk/quan.....t-systems/

    But just how hard is it to ‘suitably choose’ the initial conditions so that coherence can be maintained in proteins? Well, Doug Axe estimated that the “specific function by any domain-sized fold may be as low as 1 in 10^77”.

    Estimating the prevalence of protein sequences adopting functional enzyme folds: Doug Axe:
    Excerpt: The prevalence of low-level function in four such experiments indicates that roughly one in 10^64 signature-consistent sequences forms a working domain. Combined with the estimated prevalence of plausible hydropathic patterns (for any fold) and of relevant folds for particular functions, this implies the overall prevalence of sequences performing a specific function by any domain-sized fold may be as low as 1 in 10^77, adding to the body of evidence that functional folds require highly extraordinary sequences.
    https://www.ncbi.nlm.nih.gov/pubmed/15321723

    1 in 10^77 is just about as difficult as finding a single particle in the entire universe. But the quantum coherence of proteins makes that probability of choosing the right initial conditions even worse. Dr. Durston gives us a glimpse as to what that ‘even worse’ problem is for finding a functional protein here:

    (A Reply To PZ Myers) Estimating the Probability of Functional Biological Proteins? Kirk Durston , Ph.D. Biophysics – 2012
    Excerpt (Page 4): The Probabilities Get Worse
    This measure of functional information (for the RecA protein) is good as a first pass estimate, but the situation is actually far worse for an evolutionary search. In the method described above and as noted in our paper, each site in an amino acid protein sequence is assumed to be independent of all other sites in the sequence. In reality, we know that this is not the case. There are numerous sites in the sequence that are mutually interdependent with other sites somewhere else in the sequence. A more recent paper shows how these interdependencies can be located within multiple sequence alignments.[6] These interdependencies greatly reduce the number of possible functional protein sequences by many orders of magnitude which, in turn, reduce the probabilities by many orders of magnitude as well. In other words, the numbers we obtained for RecA above are exceedingly generous; the actual situation is far worse for an evolutionary search.
    http://powertochange.com/wp-co.....Myers_.pdf

    In other words, taking the ‘context’ of an entire protein into consideration, which is what we have with quantum coherence in proteins, makes the situation far worse from a probability perspective. How much worse? Well here is a ballpark estimate of 10^50 times worse for small molecules:

    Quantum criticality in a wide range of important biomolecules
    Excerpt: “Most of the molecules taking part actively in biochemical processes are tuned exactly to the transition point and are critical conductors,” they say.
    That’s a discovery that is as important as it is unexpected. “These findings suggest an entirely new and universal mechanism of conductance in biology very different from the one used in electrical circuits.”
    The permutations of possible energy levels of biomolecules is huge so the possibility of finding even one that is in the quantum critical state by accident is mind-bogglingly small and, to all intents and purposes, impossible.,, of the order of 10^-50 of possible small biomolecules and even less for proteins,”,,,
    “what exactly is the advantage that criticality confers?”
    https://medium.com/the-physics-arxiv-blog/the-origin-of-life-and-the-hidden-role-of-quantum-criticality-ca4707924552

    It is in realizing the staggering level of engineering that must be dealt with in order to achieve quantum coherence for each individual protein, engineering along the entirety of the protein structure I strenuously add, that it becomes apparent even Axe’s 1 in 10^77 estimate for rarity of finding specific functional proteins within sequence space is far, far too generous of an estimate.

  3. 3
    bornagain77 says:

    Of supplemental note. To be clear, quantum coherence is a ‘non-local’, beyond space and time, state just as ‘simple’ quantum entanglement is ‘non-local’, beyond space and time, state:

    Looking beyond space and time to cope with quantum theory – 29 October 2012
    Excerpt: “Our result gives weight to the idea that quantum correlations somehow arise from outside spacetime, in the sense that no story in space and time can describe them,”
    http://www.quantumlah.org/high.....uences.php

    Coherence and nonlocality
    Usually quantum nonlocality is discussed in terms of correlated multiparticle systems such as those discussed by John Bell in his famous 1964 theorem and then later clarified by GHZ, David Mermin and others.
    But more striking and significant is the qualitative nonlocal phenomena associated with coherent states,,,,
    In fact, theoretically these two kinds of nonlocality have precisely the same basis: the unmeasured singlet state uncovered by EPR is a coherent ‘pure state’ despite its spacial extension, and when the parts are realized in a measurement (a la Bell) this coherence is harvested or cashed in.
    Whereas the “EPR” connections are ephemeral and fragile, some forms of nonlocal coherence are robust.
    http://www.nonlocal.com/hbar/n.....rence.html

    In fact, “physicists (have shown) that the greater the number of particles in a quantum hypergraph state, the more strongly it violates local realism, with the strength increasing exponentially with the number of particles”

    Physicists find extreme violation of local realism in quantum hypergraph states – Lisa Zyga – March 4, 2016
    Excerpt: Many quantum technologies rely on quantum states that violate local realism, which means that they either violate locality (such as when entangled particles influence each other from far away) or realism (the assumption that quantum states have well-defined properties, independent of measurement), or possibly both. Violation of local realism is one of the many counterintuitive, yet experimentally supported, characteristics of the quantum world.
    Determining whether or not multiparticle quantum states violate local realism can be challenging. Now in a new paper, physicists have shown that a large family of multiparticle quantum states called hypergraph states violates local realism in many ways. The results suggest that these states may serve as useful resources for quantum technologies, such as quantum computers and detecting gravitational waves.,,,
    The physicists also showed that the greater the number of particles in a quantum hypergraph state, the more strongly it violates local realism, with the strength increasing exponentially with the number of particles. In addition, even if a quantum hypergraph state loses one of its particles, it continues to violate local realism. This robustness to particle loss is in stark contrast to other types of quantum states, which no longer violate local realism if they lose a particle. This property is particularly appealing for applications, since it might allow for more noise in experiments.
    http://phys.org/news/2016-03-p.....alism.html

    All of this is completely unexpected on the materialistic presuppositions of Darwinian evolution, but for a Theist is it quite a pleasant surprise. The pleasant surprise of all this ‘non-local, beyond space and time’ business, of course, being the fact that we now have fairly strong physical evidence suggesting that we do indeed have an eternal soul that lives beyond the death of our material bodies.

    “Let’s say the heart stops beating. The blood stops flowing. The microtubules lose their quantum state. But the quantum information, which is in the microtubules, isn’t destroyed. It can’t be destroyed. It just distributes and dissipates to the universe at large. If a patient is resuscitated, revived, this quantum information can go back into the microtubules and the patient says, “I had a near death experience. I saw a white light. I saw a tunnel. I saw my dead relatives.,,” Now if they’re not revived and the patient dies, then it’s possible that this quantum information can exist outside the body. Perhaps indefinitely as a soul.”
    – Stuart Hameroff – Quantum Entangled Consciousness – Life After Death – video (5:00 minute mark)
    https://youtu.be/jjpEc98o_Oo?t=300

    Verse:

    Mark 8:37
    “Is anything worth more than your soul?”

  4. 4
    bornagain77 says:

    How Einstein and Schrödinger Conspired to Kill a Cat
    The rise of fascism shaped Schrödinger’s cat fable.
    BY DAVID KAISER – OCTOBER 13, 2016
    Excerpt: In time, the challenge that Schrödinger thought would undercut quantum mechanics became, instead, one of the most familiar tropes for teaching students about the theory. A central tenet of quantum mechanics is that particles can exist in “superposition” states, partaking of two opposite properties simultaneously. Whereas we often face “either-or” decisions in our everyday lives, nature—at least as described by quantum theory—can adopt “both-and.”
    Over the decades, physicists have managed to create all manner of Schrödinger-cat states in the laboratory, coaxing microscopic bits of matter into “both-and” superpositions and probing their properties. Despite Schrödinger’s reservations, every single test has been consistent with the predictions from quantum mechanics. In one recent example, colleagues and I demonstrated that neutrinos—subatomic particles that interact very weakly with ordinary matter—can travel hundreds of miles in such cat-like states.15
    There is a double irony, then, to Schrödinger’s tale of his twice-fated cat. First, although Schrödinger’s cat remains well known within (and beyond) physics classrooms, few recall that Schrödinger introduced his fable to criticize quantum mechanics rather than elucidate it. Second, and even more telling: Schrödinger’s cat served, in its day, as synecdoche for a broader world that had become too strange—and, at times, too threatening—to understand.
    http://nautil.us/issue/41/sele.....kill-a-cat

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