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Quantum Information Can be Negative
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."
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.
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 clearance system sounds logical. It is not. It is completely arbitrary. -- John Bolton
The article calls this a measurement of the quality of the information, which they say has no bearing on the quantity. The thing about quantum information is that due to the fact that the amount of information contained can lessen by measuring the information, it is actually possible to know more about a quantum object than actually describes it. Think of it more like looking at a comet in space. You can learn more about it by hitting it with explosives and measuring the spectral result, but in doing so you are actually destroying bits of the comet. So eventually, you can know all about an object that doesn't actually exist. Of course, unlike comets, quantum objects can be both there and not there at the same time; the time factor of it being destroyed after it has been measured is effectively removed.
(I also appologize for my apparent over-use of conjunctions today :P)
But one day Tom, he went and caught the River-daughter, in green gown, flowing hair, sitting in the rushes
Sounds like BS to me. How are the slits not detectors? Anything the particle interacts with in it's path is a "detector". The more I read stuff like this, and the longer we go without any real engineering based on it, the more I think some "researcher" is spending his NSF grant on the crack he's smoking.
You clearly know nothing about quantum mechanics. The slit is not a detector because, put simply, it does not detect anything. The whole point of the double slit experiment was to show that if there are two slits, there is some uncertainty as to which one the particle went through. This is due to the interference of the wavefunctions.
Before you accuse others of BSing, learn some quantum physics. It's quite interesting.
Nope. Try +5 Insightful!
See my journal for slashdot ID's by year. Mine created in 2005. http://slashdot.org/journal/289875/slashdot-ids-by-year
All the research I have read points to PowerPoint as a better method of Negative Information storage.
A blog about stuff.
That's exactly his point, too. The OP appreciates work that is actually contributing new knowledge. His point was that the article in question is just rambling without making any significant contribution to the body of knowledge in the field.
While I'm not in quantum physics or computing, I am quite familiar with the academic problem the OP is grumbling about: There are too many papers published with too few actual discoveries. The problem is that padding one's CV is more important to certain aspects of one's professional reputation than making significant discoveries. This leads to lots of papers being written with long references sections that ramble on basically rehashing old work and making "interesting observations" about what things "might" mean. The subtext of "might" of course being that the author cannot say anything for sure, but wants to do a lot of namedropping in the process.
argumentum ad fallacium: Fallacy of defining a fallacy which allows one to dismiss the argument in question.
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.
Kind of like what happened with relativity/relativism ("everything is relative, Einstein even proved it").
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 are also almost certainly catering to popular misunderstanding in the same way the quantum "teleportation" people do. Use of common terms in a way that you know is going to be misinterpreted is bad science, does the public a disservice, and violates the scientist's obligation to spread truth and understanding rather than obscurity and confusion.
Blasphemy is a human right. Blasphemophobia kills.