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Technology Hardware

Brain-Inspired 'Memcomputer' Constructed 53

New submitter DorkFest writes: "Inspired by the human brain, UC San Diego scientists have constructed a new kind of computer that stores information and processes it in the same place. This prototype 'memcomputer' solves a problem involving a large dataset more quickly than conventional computers, while using far less energy. ... Such memcomputers could equal or surpass the potential of quantum computers, they say, but because they don't rely on exotic quantum effects are far more easily constructed." The team, led by UC San Diego physicist Massimiliano Di Ventra published their results in the journal Science Advances.
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Brain-Inspired 'Memcomputer' Constructed

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  • by msobkow ( 48369 ) on Saturday July 04, 2015 @07:58PM (#50045923) Homepage Journal

    I didn't see the point to this design until I noticed the part about it being "analog".

    Until then, I wasn't seeing the difference between the memcomputer and older non-symmetric parallel processing machines which used to cluster a CPU with it's memory for each node/board of the system, but without the shared memory of an SMP system.

    Still, I'm afraid I can't see much practical application to their system, and they don't give any examples of the types of problems they think it'll be suitable for.

    • This article reminds me of using a quantum monte carlo algorithm vs a classical monte carlo. The quantum monte carlo scales linearly with the number of trotter slices, but really a real quantum algorithm should use 2^n slices each coupled to one another. It definitely sounds like the people who are doing this research are at least 30 years behind the technological times. The biggest reason for not having all the memory directly accessible in a single processor computer is technological feasibility and cost.
    • by Anonymous Coward

      " a CPU with it's memory"

        I'm afraid I can't see much practical application to using an apostrophe there.

  • by cold fjord ( 826450 ) on Saturday July 04, 2015 @08:05PM (#50045941)

    At first I thought they might be doing some flavor of Computational RAM [wikipedia.org], but they did something rather different. The system is analog. And it is suggested memristors [hp.com] could provide useful in implementation of similar systems.

    Just a couple sections I found interesting FTA:

    As we discuss in the following paragraphs, the machine we built is analog and hence would be scalable to very large numbers of memprocessors only in the absence of noise or using some error-correcting codes. This problem derives from the fact that in the present realization, we use the frequencies of the collective state to encode information, and to maintain the energy of the system bounded, the amplitudes of the frequencies are dampened exponentially with the number of memprocessors involved. However, this latter limitation is due to the particular choice of encoding the information in the collective state and could be overcome by using other realizations of digital memcomputing machines and using error-correcting codes. For example in (8), two of the authors (F.T. and M.D.) proposed a different way to encode a quadratic information overhead in a network of memristors that is not subject to this energy bound.

    These properties ultimately derive from a different type of architecture: the topology of memcomputing machines is defined by a network of interacting memory cells (memprocessors), and the dynamics of this network are described by a collective state that can be used to store and process information simultaneously. This collective state is reminiscent of the collective (entangled) state of many qubits in quantum computation, where the entangled state is used to solve efficiently certain types of problems such as factorization (9). Here, we prove experimentally that such collective states can also be implemented in classical systems by fabricating appropriate networks of memprocessors, thus creating either linear or nonlinear combinations out of the states of each memprocessor. The result is the first proof of concept of a machine able to solve an NP-complete problem in polynomial time using collective states.

    In summary, we have demonstrated experimentally a deterministic memcomputing machine that is able to solve an N P -complete problem in polynomial time (actually in one step) using only polynomial resources. The actual machine we built clearly suffers from technological limitations, that impair its scalability due to unavoidable noise. These limitations derive from the fact that we encode the information directly into frequencies, and so ultimately into energy. This issue could, however, be overcome either using error correcting codes or with other UMMs that use other ways to encode such information and are digital at least in their input and output. Irrespective, this machine represents the first experimental realization of a UMM that uses the collective state of the whole memprocessor network to exploit the information overhead theoretically introduced in (8). Finally, it is worth mentioning that the machine we have fabricated is not a general purpose one. However, other realizations of UMMs are general purpose and can be easily built with available technology (22–26). Their practical realization would thus be a powerful alternative to current Turing-like machines.

    • http://www.scottaaronson.com/b... [scottaaronson.com]

      and can someone confirm this UMM (Universal Memcomputing Machine) is not the UMM U-MM Unbounded-MM related to RMM of the class of languages recognized by KWQFA's with cut-point (i.e. with unbounded error) of Brodsky and Pippenger 1999 paper . And I found this while trying to understand. "What is the largest probability with which a 1QFA can accept the language. in contrast to the model 1QFA discussed so far, that has been then termed as MM-1QFA (many measurements) model."

  • FPGA anyone? (Score:4, Interesting)

    by evanh ( 627108 ) on Saturday July 04, 2015 @08:07PM (#50045945)

    It sounds awfully like an FPGA just from the snippet. There have been FPGA variants that are self-reconfigurable in the past also but they fell by the wayside from lack of demand.

  • by gweihir ( 88907 ) on Saturday July 04, 2015 @08:14PM (#50045961)

    ... this is, of course, complete bullshit. Or to put it less friendly: This person is trying to con the public.

    • Another possibility is that the research has been over-hyped - the article reads like a journalist trying to describe something they don't understand to and audience they expect to understand even less.

    • Re: (Score:2, Interesting)

      What do you mean, nobody knows how the brain works? Neuroscience has made some progress over the years, you know. We might not know everything (especially once you start getting into the emergence of consciousness) but that doesn't mean no-one knows anything.

      In any case, it's entirely possible to be inspired by something while still having little to no idea about how it works.

  • low-hanging fruit.
  • by Greyfox ( 87712 )
    Stores information and processes it in the same place? You mean like every other computer ever?
    • Re:Wat? (Score:4, Insightful)

      by drinkypoo ( 153816 ) <drink@hyperlogos.org> on Saturday July 04, 2015 @10:47PM (#50046413) Homepage Journal

      Stores information and processes it in the same place? You mean like every other computer ever?

      Well, no. I didn't RTFA because I'm not new here, but ordinary computers have to copy the data from memory into a register before they can process it. They don't process it in-place. And most data is not kept in memory all the time, either, but I figured they meant the first sense.

    • by Bengie ( 1121981 )
      I've never seen a computer that does this. Most CPUs I know of use registers to store data and execution units to manipulate data from the registers.
    • Ordinary computers don't store and process information at the same place.

      Data is stored on disks, or in the cloud, loaded into memory for processing and finally processed in a processor.

      The differences are huge, go back to school!

    • You don't know much about computers, do you?

  • More shitty words we can't pronounce. Thanks a lot, science.
  • memcomputer

    That sounds like something out of Fallout New Vegas. Like Mr House would have a "memcomputer" keeping his accounts.

    The nerds at UCSD are gonna have to work on the name to sound a little less 1950s. Or maybe that's what they're going for?

  • by K. S. Van Horn ( 1355653 ) on Saturday July 04, 2015 @10:59PM (#50046459) Homepage

    Good Lord, people, Scott Aaronson refuted this memcomputer nonsense some time ago:

    Memrefuting [scottaaronson.com]

    The short story is that all they've done is a sleight of hand where they smuggle the exponential blowup somewhere else.

    • Parent post is the only post needed in response to this story. If even a quantum computer can merely get a polynomial speedup in the best case, it's kind of silly to suppose that a classical analog computer can get an exponential speedup. And what really grinds my gears is the implication that superturing computation might be possible, which would violate the Bekenstein bound.
    • by tgv ( 254536 )

      Interesting. If you liked the OP, this is a must-read.

    • Re: (Score:3, Interesting)

      by ExekielS ( 4130459 )
      I'm not an expert on this topic, but reading that article I notice it claims that the paper does not provide an alternate method of encoding information when the article does exactly that and provides a digital means of handling it. I don't know if their claim is plausible, but this "refutation" seems weak at best, given everything it ignores.
  • They invented a processor with level 1 cache? WOW! I assume they phrased it incorrectly and in reality it does computing logic in the RAM, not stored the data inside the processor....like modern processors do.
    • They invented a processor with level 1 cache? WOW!

      No, they didn't.

      I assume they phrased it incorrectly

      I assume you skimmed the article, didn't really understand it, but figured you could still get away with sounding condescendingly intelligent to around 50% of Slashdot readers.

  • This is pure BS (Score:4, Interesting)

    by vikingpower ( 768921 ) on Sunday July 05, 2015 @03:33AM (#50047029) Homepage Journal

    all frequencies involved in the collective state (1) are dampened by the factor 2-n

    And this is where they stuff away the rabbit they pretend to be pulling out of the hat. For any moderately sized, non-trivial SSP ( Subset Sum Problem ), this brings down the produced output signal's readability to being so hard to detect that you need exponential time to decide upon a reading. Which debunks this entire piece of bullshit in one phrase. 'Nuff said, OP is BS. QED.

  • What's wrong with memputer?

You know you've landed gear-up when it takes full power to taxi.

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