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back to article Quantum computers have failed. So now for the science

I am a heretic. There, I've said it. My heresy? I don't believe that quantum computers can ever work. I've been a cryptographer for over 20 years and for all that time we've been told that sooner or later someone would build a quantum computer that would factor large numbers easily, making our current systems useless. However …

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    1. Paul Kinsler
      Reply Icon

      Re: analog analogies

      Let me just strongly endorse the fourth paragraph above, namely "Similarly, if someone finds a physical model which mimics many of the facets of quantum mechanics, that doesn't mean that it can be used to predict or prove how things work in the quantum world."

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      1. DropBear
        Reply Icon
        WTF?

        Re: analog analogies

        It doesn't mean that said physical model can't be used to predict any number of further similarities between the model and the real world either. We don't know until we use that model to try to gain new insight, predict something and see if it fits the facts...

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    2. Paul Smith
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      Re: analog analogies

      QM theory was developed to describe phenomena that could not be explained by classical means, so the thing I take from this is that having a physical model displaying features previously only visible in the QM world removes (some of) the need for a quantum specific theories and moves us closer to a theory that joins both worlds. If, in the process, we happen to get rid of some of the 'dafter' aspects of modern physics (cough, strings, cough), then all the better.

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  2. Destroy All Monsters Silver badge
    Pint

    Yet another tiresome attempt at banging the round peg of QM into a square, classical hole

    Im too lazy to pursue the classical handwaving into adequate equations, but I notice the FAIL at the last sentence:

    And if reality is analogue all the way down, then quantum computers are just analogue computers, so their failure to deliver magical results is unsurprising. In fact, we'd rather see it as evidence that the emergent quantum mechanics research community may be on the right track.

    Their "failure to deliver magical results is unsurprising", really?

    First of all these results are not magical and of course they are analog. The "failure to deliver magical results" has to do with adequate production processes. No-one has yet said "that's odd" because the machine magically fails (which would be interesting). It isn't even big enough yet to exhibit such an interesting effect.

    Not so long ago it was not at all clear that large digital machines could be constructed because errors due to stray voltages and flaky vaccum tubes may well propagate and swamp the delicate computation of the state machine. Amazingly, it was all solved and no-one except overclockers give this problem much thought today.

    Also, Scott Aaronson in Collaborative Refutation.

    "Third thought: it’s worth noting that, if (for example) you found Michel Dyakonov’s arguments against QC (discussed on this blog a month ago) persuasive, then you shouldn’t find Anderson’s and Brady’s persuasive, and vice versa. Dyakonov agrees that scalable QC will never work, but he ridicules the idea that we’d need to modify quantum mechanics itself to explain why. Anderson and Brady, by contrast, are so eager to modify QM that they don’t mind contradicting a mountain of existing experiments. Indeed, the question occurs to me of whether there’s any pair of quantum computing skeptics whose arguments for why QC can’t work are compatible with one another’s. (Maybe Alicki and Dyakonov?)

    But enough of this. The truth is that, at this point in my life, I find it infinitely more interesting to watch my two-week-old daughter Lily, as she discovers the wonderful world of shapes, colors, sounds, and smells, than to watch Anderson and Brady, as they fail to discover the wonderful world of many-particle quantum mechanics. So I’m issuing an appeal to the quantum computing and information community. Please, in the comments section of this post, explain what you thought of the Anderson-Brady paper. Don’t leave me alone to respond to this stuff; I don’t have the time or the energy. If you get quantum probability, then stand up and be measured!"

    Beer to that, Scott.

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    1. Anonymous Coward
      Reply Icon
      Anonymous Coward

      Re: Yet another tiresome attempt at banging the round peg of QM into a square, classical hole

      The analog substrate which supports the computing mesh, or whatever we perceive as quantum mechanics, will be subject to some form of ultraviolet catastrophe, except we probably won't be able to conduct experiments on it, unlike renormalization in Yang-Mills QFT. So the theory may not be falsifiable.

      Of course we can always resort to supernatural hand-waving to dismiss such concerns - infinite mind of God, turtles all the way down, etc.

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    2. Destroy All Monsters Silver badge
      Reply Icon
      Headmaster

      Re: Yet another tiresome attempt at banging the round peg of QM into a square, classical hole

      Or this

      You don’t get to replace the precise predictions of QM by slippery verbal reasons-why-you’re-not-yet-proven-wrong that change from one experiment to the next. Instead, you need to replace QM by an alternate mathematical theory that

      (1) also describes anything that could possibly happen to a many-particle quantum system (not just one particular thing),

      (2) agrees with all experiments that have already been done, but

      (3) unlike QM, does not require an exponentially-large Hilbert space.

      YOU HAD ONE JOB. "Quantum computers have failed. So now for the science" doesn't even manage to get the pants up.

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    3. Anonymous Coward
      Reply Icon
      Anonymous Coward

      Re: Yet another tiresome attempt at banging the round peg of QM into a square, classical hole

      Your comment about large digital machines is incorrect in that first noise wasn't the issue and second the reliability problem was addressed quite quickly, beginning I think with the EF50 in the UK. Noise became a problem with the first drum storage but by then the machines worked. There was no argument about whether they were actually computing.

      Quantum computing is proving a very intractable problem. It may be proven workable but the boring old gate based stuff seems to winning the race at the moment.

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  3. Graham Marsden
    Coat

    It's quantum...

    ... that means it both will *and* won't work...

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    1. Mark 85
      Reply Icon

      Re: It's quantum...

      Would not that depend upon which universe you're in... or not in?

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    2. razorfishsl
      Reply Icon

      Re: It's quantum...

      Incorrect...

      It actually means its state is undetermined until it is observed.

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  4. x 7

    So I suppose that instead of looking for "god in the machine" we should be looking for "god in the virtual machine"........I threw that phrase into google translate to see what the latin would be and got......

    "deus in rectum apparatus"

    is someone trying to tell us something about experimentation?

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  5. bep

    So as I understand it,

    we're back to waves travelling in an invisible, undetectable aether? That doesn't sound so hot, but when the other mob have to resort to Dark Matter AND Dark Energy and still wind up with multiverses, the funny old aether doesn't seem so out of order.

    Enjoyed the article a lot, but as Homer Simpson said...

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    1. Anonymous Coward
      Reply Icon
      Anonymous Coward

      Re: So as I understand it,

      There is a simple problem with the aether; it was disproven by the Michaelson-Morley experiment, and indeed if it exists bang goes relativistic physics.

      Aether needed to be a vector field to work. That doesn't rule out a scalar field that permeates all space if there is no preferred centre or direction, but it wouldn't be the aether.

      Dark matter and dark energy aren't a conceptual problem - the idea that there exists mass and energy that do not interact with the EM field is no odder than the proven existence of neutrinos, which almost don't. If you had a dark room whose floor was covered in red, green and blue balls mixed in with a lot of matt black balls, and were allowed to investigate by shining a narrow beam of light into the room, it might take some time before you discovered the black balls. Neither of them implies a multiverse.

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  6. Anonymous Coward
    Anonymous Coward

    Very nice article. More please.

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  7. PleebSmash
    FAIL

    cool opinion

    Says quantum computers can't ever work.

    Admits three qubit versions work.

    What's this, 9 qubits?

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    1. jzlondon
      Reply Icon

      Re: cool opinion

      You beat me to it.

      If three qubits works, that shows there's no fundamental problem. Just a question of implementation.

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  8. Huckleberry Muckelroy

    Analogue slow?

    Quantum computing always impressed me as vaporware. However, your throwaway line "...but it would just be an analogue computer, so you couldn't expect any magical speed-up." really has no moxie behind it. I think that analog should take off because we already have experience in it, both as man-made, and our own brains. We only started all that binary digital computing cock-up because it was so EASY.

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    1. Anonymous Coward
      Reply Icon
      Anonymous Coward

      Re: Analogue slow?

      Animals must decide discrete sequences of actions to perform in response to their immediate environmental situation. They cannot flee, fight and remain motionless at the same time. There must be positive feedback or attractor state mechanisms in the brain to cause switching. Well, switching is a digital term. That is not to say the brain is a digital CPU. Rather it is a digital recall system. Recalling required sequences of actions, remembering which worked out well and which did not and therefore updating itself.

      I have reasons to believe the human brain is about 100 Gbytes. Instead of IQ I think it would be better to measure the amount of Gbytes a person is. So a person with an IQ of 100 with a lot of experience in the world would have more Gbytes than a person with an IQ of 130 who had spent his or her whole life working the fields or sell tea on the side of the road in a developing country.

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  9. Anonymous Coward
    Boffin

    Hidden variable

    This 'long range order' is what is known as a 'hidden variable': such theories have been known about for a long time as have their problems. There is nothing new here, other than The Register printing fringe science articles.

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  10. Anonymous Coward
    Anonymous Coward

    The monkeys are at it again

    [wavy vague cone, M16.73, tra. @n3.27.337.1337]

    xLSV Syntax Error

    oGCU amanfromMars 1

    This is not our circus; these are not our monkeys.

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    1. Ashton Black
      Reply Icon

      Re: The monkeys are at it again

      [tight beam, M32, tra. @n4.28.885.1008]

      x(d)ROU Put a Sock in it.

      oLSV Syntax Error

      Awww, you're no fun! Let him play!

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  11. Anonymous Coward
    Anonymous Coward

    Long-range order? oscillation?

    http://www.youtube.com/watch?v=ilf08z6J2AQ

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  12. Benjol

    Impressive marketing budget if they can get God presenting their video...

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  13. distimpson

    spooky bell

    thanks for crushing the false hopes and dreams of the younger generation. there's this too: http://youtu.be/lOT38L1utw8

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  14. imanidiot Silver badge

    Despite all the bitching above

    I still found it an interesting read and I hope we get more like it in the future!

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  15. rchop

    Quantum phenomena

    Has anyone considered that the super-fluid might be the sea of virtual particles that fill a vacuum?

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  16. GrumpyMiddleAgedGuy

    My theory is that it is elephants the whole way down. So where does the first elephant contact earth - North Korea. Why else would they keep the lights out at night... It's all a giant conspiracy.

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  17. Anonymous Coward
    Anonymous Coward

    Isn't this all known to be rubbish?

    To quote the MIT quantum computing expert Scott Aarsonson..

    " The hydrodynamic models still can’t correctly reproduce the effects even of two-particle entanglement, Bell’s inequality still explains precisely why no such model will ever be able to do that, and the advocates of the models still can’t formulate a way around Bell’s inequality that makes the slightest bit of sense to those who understand it. Which means that there’s no need even to discuss quantum computing; the proposed classical description of our world fails way before we get there. Move along, folks."

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    1. Anonymous Coward
      Reply Icon
      Anonymous Coward

      Re: Isn't this all known to be rubbish?

      Are the people who are voting down saying that the quantum computing MIT professor is wrong about quantum mechanics? If so, why?

      My understanding is that Brady and Anderson have been trying to claim they have reinvented quantum mechanics for a few years now and all respectable physicists who have looked at their claims say it is nonsense.

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  18. Paul 129
    Thumb Up

    NICE

    I've been fascinated at those silicon droplet experiments too. It makes you look at all the old experiments into Aether. All cool stuff. I too expect that there is something that we are missing that will move us into a more classical interpretation.

    The flow on effects into quantum computing....

    You have to know what information your missing, and that is the crux of the issue ;-)

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  19. John Savard

    Doubts

    As the Schrodinger equation is a wave equation, it is not too remarkable that some of its behaviors can be replicated in other things that involve waves. If, however, you ever try to do the Bell's inequality experiment with your droplets, I rather think that some differences will come out - indeed, I suspect that they will manifest themselves earlier, such as when you try to "observe" those droplets, thus forcing wave packets into eigenstates.

    The wave-particle duality is key to much of the strangeness of quantum mechanics. Yes, you can simulate the wave part, but the particle part, that leads to "quantization", is not so easy to match with a classical model.

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  20. Werner McGoole

    Testing, testing...

    So if I read the article correctly, the existence of a quantum computer would serve as experimental refutation of this theory. These days it's good to find such a simple experimental test of a new theory in physics - and such a well funded one too!

    Personally, I'd have to agree with Richard Feynman's original observation that, essentially, the universe has to be able to compute a lot faster than our classical computers do or it wouldn't be able to work fast enough itself. Quantum computing is just a way of harnessing the computing that goes on around us all the time - and it's staggeringly fast.

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  21. djolds1

    For an existing, long-range order... consider Weyl geometry. Essentially produced Schrodinger's wave equations from first principles about a century back. Einstein's non-integrability objections are resolved by setting the scale factor to unity.

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  22. Anonymous Coward
    Anonymous Coward

    cowarding arround

    How could quantum computers connect Qbits using our usual crafting abilities ?

    To be usable, this has to be built in some extended dimensions which we still cannot kraft.

    By the way ... did someone try to put half of a very small ball of nuclear fuel waste (especially U238) in a pretty good laser boiler (like the NIF for instance) while recording the tap tap made by a Geiger counter surrounding the other half ? (the ball would be made of a small vaporized/condensed part of a precise point of a used nuclear fuel stick)

    Entangled U238 atoms would be interesting I guess.

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  23. Jim99

    human brains

    If quantum computers are physically possible, wouldn't the human brain be a quantum computer? If it isn't, then maybe they can't exist?

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  24. vzn

    Anderson/ Brady are the pioneers with arrows in their backs

    hi RA think this is dead on but it could take many, many years for the mainstream physics community to accept some of these ideas. it represents an massive structural/ kuhnian paradigm shift. QM "interpretations" have been settled by the mainstream (or rather managed to be effectively/ practically pushed aside) for nearly an entire century at this point by the so called "shut up and calculate" contingent.

    recently wrote up a lot of related info/ survey at this link

    https://vzn1.wordpress.com/2015/01/26/superclassical-emergent-qm-recent-developments-rough-outline-overview-leads/

    see esp the very recent paper on Pilot Wave Hydrodynamics by John Bush at MIT cited there. are you in contact with him?

    also another really great recent book on this is called "how the hippies saved physics" by kaiser. it shows that bells thm was not even noticed/ accepted much by the mainstream establishment for many years & was given attn by a small band of iconoclasts/ contrarians/ minority etc.

    encourage anyone interested to join stackexchange for lively chats on this & related subjects (eg physics or computer science sections etc).

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  25. Anonymous Coward
    Anonymous Coward

    UK government invests in Transputer. That one didn't work out either. It's unfortunate because there is a lot of real science pouring out of UK labs. To the point where the UK is only able to commercialize a fraction of it. Most other countries are not in that situation. You are throwing away your advantages. If you are talking about magic cats and the like then not enough is know about the basics of the subject to do real work with it.

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  26. J Perezchica

    I can see how this explains quantum entanglement

    So it appears that the long-range order you speak of (the object that connects two distant particles or oil droplets) is the vibrating field. In this way, the particles aren't necessarily entangled with each other, so much as responding to the same field that is acting on them.

    This is interesting, because it means two entangled particles aren't really entangled, just responding to the same field of a given vibrational frequency. When two or more particles become un-entangled, does that mean then that the initial particles enter different fields, each possessing a different vibrational frequency, and thus allowed to do unrelated things from one another? Seems like it!

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