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Math Science

Quantum Information Can be Negative 445

nerdlygirl writes "In a development that would probably even puzzle Claude Shannon, information can be negative -- at least when the information is quantum. The discovery, by Horodecki, Oppenheim, and Winter, appears in the current edition of the leading journal Nature. If I tell you negative information, you'll know less. Apparently, researchers hope to use this to gain deeper insights into phenomena such as quantum teleportation and computation, as well as the very structure of the quantum world. More details can be found here and here A popular account of the article can be found on Oppenheim's homepage, and a free version of the article can be found in the arxiv for those of us without subscriptions to Nature."
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Quantum Information Can be Negative

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  • by denissmith ( 31123 ) * on Monday August 08, 2005 @06:54PM (#13274292)
    Karl Rove has known this for years.
    • Re:This is not news (Score:3, Informative)

      by sratbot ( 906134 )
      FTFA: "It sometimes seems that we become more ignorant after talking to certain individuals. Perhaps they are saying things which are confusing or untrue. Well, after getting negative information, you know less. But not in the same sense as someone who tells you lies are tries to bamboozle you. Remember, that we don't worry about the quality of information (whether it is true or false for example). We just concern ourselves with how much there is. So, if we know less after receiving negative information, th
    • by Anonymous Coward
      But it does explain why my ears bleed every time I read software API documentation.
    • Well, you hit the gist of where pretty much everyone was going. Good example.

      I think another example would be religions.

      Or the classic Billy Madison line "we are all now stupider for having listened to that" (not sure if I phrased that exactly but it's very close to that).

      But you can look at pretty much anything in society and see this being used all the time. Look at how many people think things like Universal Health Care is bad, Schools need local control, taxes are always bad, paying off national debt
  • nope (Score:3, Funny)

    by cain ( 14472 ) on Monday August 08, 2005 @06:54PM (#13274293) Journal
    No it can't.
    • Yes it can (Score:3, Informative)

      by Anonymous Coward
      This article is not bogus.

      The concept of a "quantum eraser" is not a new one. Consider the classic double-slit experiment, where electrons are shot at a double slit and form an interference pattern on a screen which corresponds to the probability distribution of the particle's position. If you were to place detectors so that you knew which slit the particle went through, the interference pattern would disappear-- that is, there would be no uncertainty in the position (because obviously, you know which slit
      • I bet it might make a REALLY good encryption trick, too!
    • I feel dumber for having read your post.

      Although, this just goes to prove the point I always made when I was sitting through mind numbingly boring lectures given by stupid people in the past... "i feel dumber for having sat through that". Now I knot that I wasn't just imagining it!
  • by Skyshadow ( 508 ) * on Monday August 08, 2005 @06:54PM (#13274294) Homepage
    I've been studying negative information for years. I consider myself somewhat of an expert on the subject, actually.

    Initially, I believed that negative information was an abstract math concept, but after a significant amount of additional study I've determined rather conclusively that it exists in our frame of reference and that the effects are actually easy to detect. The trick is to *locate* some of this negative information. Fortunately, I've managed to work that out as well -- I'm not publishing for a few months yet, but I figure I'm far enough along to spill some of the beans:

    Experiencing negative inforamtion is all about occupying a point in space and time which intersects with the negative information stream. This was initially tricky, but through months of tireless research I've worked out the optimal conditions: I find that your best chance of encountering it is roughly around 1 AM when you're at the bar with your friends after a long night of drinking and one of them says something along the lines of, "Awright! Time for some shots!"

    Bang! Negative information. What happened after that? How did I get home? All lost in the quantum flow, never to be accurately described by anyone involved (except, occasionally and for reasons I still haven't managed to factor into my equations, the bouncer and the police). I assume the headaches and liver damage are just a nominal side effect.

    • Browse at -1
    • The Fine Article doesn't mention one exciting development in the field of information theory, related to negative information, which may one day tie it to Vacuum Energy [] or Zero Point physics [] in a grand unified theory that, once we come to understand it, could form the basis of a star drive to power star ships. []

      It seems that virtual particles of antimatter and exotic particles of normal matter that spontaneously emerge from the void, and then disappear without interacting with anything. [1] The theoretical potential of tapping this particle flux has brought vacuum energy to the fore of research by the NSA into Quantum Information Theory.

      Experiments conducted by the NSA and the DOE on large data samples gathered in large bureaucracies (both public and private) indicate that Microsoft Word Documents are effective containers for Negative Information, which hitherto had been considered a transient phenomenon, almost impossible to store given our current understanding of physics. The phenomenon of massive amounts of stored negative informisinformation, as it turns out, makes the typical corporate or government intranet much more resiliant to cyber terrorist attack than previously predicted -- nearly as resiliant as the typical government organization to a FOIA request today, for comparison.

      It is expected that once we understand the characteristics of MS Word Documents which allow them to efficiently store negative information in a stable form, Quantum Physicists and Information Theorists should be able to get together, perhaps over a nice hot cup of tea, and stitch the two branches together, getting us one step closer to faster than light travel, finally bringing the stars within reach -- except it won't really be FTL, it will be something that we don't presently understand. [2]

      Only the humor-impaired need read this bootnote.
      [1]Yes, I see the grammar error. I've intentionally borrowed a pattern, common in conspiracy theory writing, of constructing a complex sentence, perhaps full of objects, perhaps full of verbs, perhaps full of nouns, on the theory that it might amuse, whereas it normally serves to confuse, as sometimes subjects or verbs may go missing. Oops I did it again! Or did I?
      [2]Yes, I realize I mention antimatter only in the title, and not in the text.
      [3]Yes, I realize there are 3 bootnotes, not a single bootnote as referenced above.
      [4]Yes, I realize that only 2 of the bootnotes are indicated by reference numbers in the text. (Absurd bootnotes are also common in conspiracy theorist writings.)
  • by 77Punker ( 673758 ) <> on Monday August 08, 2005 @06:54PM (#13274295)
    If I tell you negative information, you'll know less. Sounds like what happened in that mind numbing English class I had to take last semester.
  • by mrsbrisby ( 60242 ) on Monday August 08, 2005 @06:54PM (#13274296) Homepage
    it was negative information so I forgot how to get my socks in the dirty clothes.
  • True (Score:5, Funny)

    by M.C. Hampster ( 541262 ) <> on Monday August 08, 2005 @06:54PM (#13274297) Journal
    After trying to read those articles, I do feel like I know less.
    • by Anonymous Coward
      You should try browsing at -1 sometime! You'll wish you knew less...
  • Considering some of the posters here, I wouldn't be surprised if that were discovered.
  • by multiplexo ( 27356 ) * on Monday August 08, 2005 @06:55PM (#13274311) Journal
    a friend and I used to joke that there were people who gave off destructive mental interference waves. Sitting next to these people would result in a decrease in brain function because their brainwaves were 180 degrees out of phase than the brainwaves of normal people, thus cancelling them out and creating a thought-free zone.

    Of course negative information is cool, but it would be even cooler if you could combine negative information and positive information to produce a huge explosion.

  • by djupedal ( 584558 )
    If I tell you negative information, you'll know less.

    So, if two people tell me negative information, I'll know more?

  • If I tell you negative information, you'll know less.

    I experience this almost everytime I speak to my boss.
  • "If I tell you negative information, you'll know less."

    This is nothing new, the effect is known as 'the dumbening.' It can be easily reproduced in the home by watching Harold & Kumar go to White Castle. Watch that movie, and I guarantee you'll know less!
  • Affects black holes! (Score:5, Interesting)

    by sconeu ( 64226 ) on Monday August 08, 2005 @06:56PM (#13274320) Homepage Journal

    Since a black hole's entropy is directly proportional to it's information content, this, if true, would have an effect on black holes.

    If I recall correctly (and I may not -- my physics isn't what it used to be), the amount of information contained by a black hole is directly proportional to its surface area -- specifically, I believe that the total number of bits contained is equal to 1/4 of its surface area as measured in Planck units.

    Now, if information can be negative, that would provide another method of shrinking a black hole, in addition to Hawking radiation.
    • the amount of information contained by a black hole is directly proportional to its surface area

      I didn't cover black holes in much detail, but that certianly makes sense - the surface area of a black hole would be proportional to its mass, which in turn is a function of the amount of mass it's captured, and mass capture would be the way that it captured information. (Where for the purposes of this discussion (and most discussions of this sort :-) ), mass and energy are interchangeable - so captured photons
  • If I tell you negative information, you'll know less. Apparently, researchers hope to use this to gain deeper insights into

    So less really is more?
  • It's got negative information in it!
  • Bad Analogy (Score:5, Insightful)

    by ravenspear ( 756059 ) on Monday August 08, 2005 @07:00PM (#13274359)
    If I tell you negative information, you'll know less.

    I don't think that really works. You can't make someone know less by just telling them something, unless by doing so you somehow alter their brain chemistry to store less information or remove information already stored. I suspect this might be closer to the quantum idea.

    Suppose you have two pieces of quantum information, one positive and one negative. The negative piece could negate the positive one which would result in 0 total pieces of information instead of 2.

    However, the idea of this negative information is still kind of abstract and not that easy to understand. The quantum nature of this is key I think. It doesn't look like it extends that well to our concept of information (which would be the kind stored by the brain), at least not yet.
    • The abstract says all:

      If the partial information is positive, its sender needs to communicate this number of quantum bits to the receiver; if it is negative, the sender and receiver instead gain the corresponding potential for future quantum communication.

      At risk of oversimplifying, negative information is information that is not known, but soon will be. It's not unlike what we would think of as a prediction, or more accurately, a premonition.
    • but maybe it could happen every day, lets say.

      I know 1+1=2, what if someone convinced me 1+1 infact made 3? Surely I would know less information no?
  • "Apparently, researchers hope to use this to gain deeper insights..."

    Taking into consideration the sentence before that, it seems like the hope of those researchers is unfounded... Irony.
  • by gmuslera ( 3436 ) on Monday August 08, 2005 @07:04PM (#13274387) Homepage Journal
    "One thing only I know, and that is that I know less than nothing" - Socratum
  • If I tell you negative information, you'll know less.

    So, American television programming has been giving us negative information
    for decades now....

  • First off, QM isn't the easiest subject; even experts say that if you say you understand QM (as oposed to just apply it) you're lying.

    So first off you need an understanding of QM (it's statistical information, so screw the Kopenhagen interpretation :P). Then you need to understand the concept of information, in the context of QM. After that you need to know what's meant by /positive/, in the context of information and in the context of how a Quantum Mechanic would apply that. And then you'd need to read the
    • If you absorb enough negative information, will that collapse your head?
    • At least one (Score:4, Informative)

      by Quadraginta ( 902985 ) on Monday August 08, 2005 @07:44PM (#13274690)
      Geez, don't be so cynical. After I got my PhD from Berkeley, with a dissertation in quantum mechanics, I taught the stuff to graduate students for five years or so. I've published QM papers in PRA and all that, too. So, yeah, I know what they mean. I'm perfectly qualified to review their Nature paper, if it comes to that, and I doubt I'm the only one like this reading /.

      I have to say I'm not especially impressed by the work, however. The frisson of defining information as negative emerges ultimately from a semi-deliberate muddling of the distinction between the definition of information in the quantum computing context and information as we use the word in daily life. This is not hard useful scientific discovery so much as the scientific equivalent of making an outrageous pun.

      But then I feel similarly about most of what's published in the Bell's Inequality, EPR paradox, quantum tele-whatever field. Getting cynical myself, maybe I am....bah, humbug...grumble...
      • Re:At least one (Score:3, Insightful)

        by radtea ( 464814 )

        This is pretty much my reaction, and I have a similar background.

        It has been known for a long time that quantum information can be negative. But no one has known how to interpret it. These guys are giving one possible interpretation out of the infinitely many possible ones. It is a good interpretation as it has some operational significance, but I've always found interpretive papers to be less than satisfying as science (which is why I've never published one, despite having some interesting ones.)

        They ar
        • Re:At least one (Score:3, Informative)

          by quantfreak ( 906526 )
          I am also a researcher near to this field, and actually heard it presented at a conference a few months back. The reaction of the people I know (who actively do research in this area, more so than myself), was one of extreme excitement. I think perhaps you don't understand the result.

          Quantum information is not a question of interpretation -- it is well known what it is, in terms of communication theory. What these guys did, is prove how much communication was required to send information, if the receiv

  • What you've just said is one of the most insanely idiotic things I have ever heard. At no point in your rambling, incoherent response were you even close to anything that could be considered a rational thought. Everyone in this room is now dumber for having listened to it. I award you no points, and may God have mercy on your soul.
  • That explains all those lecturers I had that would put me to sleep instantly...and I would wake up a few hours later completely clueless until I had a few beers...
  • "If it weren't for my horse, I wouldn't have spent that year in college."

    That, plus any other saying that makes the listener dumber.
  • All this time I wondered how so many people could be so stupid as to believe the mountains of bullshit pushed by the creationist movement, and this explains it!

    As information regarding the field of biology -- specifically in the study of evolution -- increases, a balance must be made. As a result, the increase of information in biology causes a reaction of an equal increase of negative information with respect to the creationist movement. The more biologists figure out and the more knowledgable experts become, the dumber and more gullible the general populace must become to balance the information flow out.
    • I would just like to point out, as a biologist and a Christian, that these two fields are not mutually exclusive. I firmly believe in creation, and I am facinated by the science I am constantly learning, but neither field rules out the other. I'm sure some believers have seriously mishandled debates to this effect, and for that I appologize, but I would beg you to remember that we are all human and subject to error.

      (I also appologize for my apparent over-use of conjunctions today :P)

    • I want to moderate this up because I think it's both funny and poignant at some level, but I can't do it in light of the poor delivery.
  • by benna ( 614220 ) <mimenarrator@g m a i l .com> on Monday August 08, 2005 @07:09PM (#13274434) Journal
    He wrote, "The scholar learns something every day, the man of tao unlearns something every day, until he gets back to non-doing."
  • I always feel like I know less after reading Darl's various enlightenments....
  • ...having things that act like negative probabilities. For example the classic two slit experiment shows that we can make it less likely for a particle to travel from A to B even though we have increased the number of paths by which it can travel from A to B. I'm not terribly suprised, therefore, by the existence of negative information.
  • So if we can figure out a way to manipulate this could we not "erase" someones memory? Isn't it possible that we already know all about this yet our memories may have been effected in some way?

    I haven't RTFA (yet) but this seems one of them "If we saw invisible people would we even know?" type questions..
  • Negative information? Doesn't that happen when one watches TV? I swear I get stupider every time I turn it on.
  • "If I tell you negative information, you'll know less."

    Anyone who watches any of the 24 hour cable news networks should know this by now. Well, they probably don't because I'm guessing it's hard to observe information loss...because you won't remember it. This is probably redundant by this point thought, huh?
  • Math (Score:3, Insightful)

    by Mark of THE CITY ( 97325 ) on Monday August 08, 2005 @07:20PM (#13274522) Journal
    Would it be accurate to analogize this to antimatter, in the sense that the latter was found mathematically first, and observed later (and maybe not yet)?
  • The question is does transmitting negative information from point A to point B cause the informantion level of A to increase? If so it would explain how universities work.

    Simply put they bring in the best and brightest students, hire professors to send these students negative information in their lectures and writings, and thus the university gains information.

    Keep this up for a couple of hundred years and it is quite obvious how top universities become famous as such great centers of learning.
  • by mbone ( 558574 ) on Monday August 08, 2005 @07:23PM (#13274544)
    I distinctly remember a lecture by Feynman at Caltech in the early 1980's where he talked about negative information (probability). I am sure I still have notes for it somewhere. Of course, you can never see negative information; any actual measurement has to have positive probility. But it can give quantum interference effects in measured quantities.

    Feynman presented it as just a different way of having quantum interference, from negative probability instead of complex amplitudes.
  • From this []: I will mention three ways of understanding negative information. Both are just rough analogies, but they kinda make sense (hopefully).

    It looks like the author's already experimenting with negative information...

  • Fox News Network.
  • If I watch TV, I become stupid, hence TV is a quantum information device.
  • ...wants to be enslaved?
  • Escort Web Pages (Score:3, Interesting)

    by pyrrhonist ( 701154 ) on Monday August 08, 2005 @07:37PM (#13274641)
    From the author's homepage:
    This web page has about 2500 English words, so it is
    convoying more information (although I can't speak to the quality of that information).
    But English is a very silly language...

    That's not really how you use that word. His spell checker must have provided negative information.

  • This is like Lavinsky's theory of the antibrain. The idea (if I recall correctly) is that bad habits are encoded in some parts of the brain. With selective drug abuse or drinking, we can selectively destroy the antibrain that usually opposes our "better half", canceling out the "good brain". So destroying antibrain is equivalent to creating brain. It's like drinking to forget - forgetting to drink too much. I'll drink to that!

    Have I told you about Lavinsky's theory of the antibrain? Stop me if you've heard
  • Negative information is how you erase data on a quantum storage device.

    To erase data on a Quantum storage device, you only need an electromagnet or a hammer.
  • I wish there was a filter for "Abuse of Modern Physics". Anyone want to explain what the article's *really* talking about, minus the stupid jokes? Wikipedia's a bit terse for something this high-level.
  • by iabervon ( 1971 ) on Monday August 08, 2005 @08:02PM (#13274823) Homepage Journal
    The trick is that you can use quantum entanglement to have excess unspecified knowledge, which can be converted into specific knowledge. It's like being on a quiz show where you are given a certain number of times you can look up an answer. These bonuses have to count in your total knowledge (I know 100 facts, plus I can look up things twice). If someone tells you something, you get positive information. If you look something up, you get zero information (you trade a bonus lookup for a fact). If you look something up, and you already knew the answer, you get negative information.

    Now think about it as if someone else controlled the book. They can tell you things over the phone, and they can cause answers to pop out of the book. If they waste the book on something you actually already knew, your total information goes down, so the information in the transaction is negative.
    • think about it as if someone else controlled the book. They can tell you things over the phone, and they can cause answers to pop out of the book. If they waste the book on something you actually already knew, your total information goes down, so the information in the transaction is negative

      Nicely explained. Thanks.

  • by lawpoop ( 604919 ) on Monday August 08, 2005 @10:06PM (#13275492) Homepage Journal
    IANA Physicist, and I'm terrible at math. But I think I have this figured out.

    In order to learn something, you have to make a measurement. Of course, in the quantum world, measuring a system will change it, so you are giving up what you know by measuring. It seems that in negative information situations, you are giving up your certainty in order to measure something, but your aren't learning anything in return. So your net 'gain' of information is negative.

  • by gearmonger ( 672422 ) on Tuesday August 09, 2005 @01:51AM (#13276367)
    Utter ignorance is the total lack of information, or the complete absence of knowledge. We all know that nowledge is power, and power is force over time. Time is money, so knowledge is force over money. Ergo, someone who is ignorant has no force over money, which is certainly ironic given that the Nature article is entitled "Quantum Information: Putting certainty in the bank". Yes, poor people are easy to make fun of even in quantum states (which were formally known as blue states until the manic depressives complained about trademark infringement).

A committee is a group that keeps the minutes and loses hours. -- Milton Berle