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Single-Photon LED: Key To Uncrackable Encryption?
nut writes: "The BBC are carrying this story of new type of LED so precise that it can emit just one photon of light each time it is switched on. It has been developed by scientists from Toshiba Research Limited and the University of Cambridge. It is described in the journal Science, although I can find no mention of it on their website. One of the applications of this is supposedly uncrackable encryption, due to the law of indeterminacy. This application is described fully in 'The Code Book', by Simon Singh, although the method was only theoretical at the time the book was first published."
And as far as I can tell, this is only a silly little theory. So far they've figured out how to emit one photon, but they don't know how to read it. I'm sure that this is gonna be HUGE...
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IMO a single photon doesn't qualify as "Light".
Calling that a LED would be like taking something that emitted single H2O molecules and calling it a tap!
Bah humbug.
I have no desire to keep on kooking. :-) That I am utterly convinced of something I cannot adequately argue is driving me *hard* to learn the necessary physics to address the topic reasonably.
:-)
:-)
But I'll do a braindump, if only to see your reaction. Warning: Unbridled speculation based off a single plausible postulate follows.
It's an interesting corrolary from crypto research that you can never be entirely sure a data source is truly entropic, as opposed to the output of even an adequately designed pseudo-random number generator. (Take a look at RC4 -- something that takes that little code to implement could certainly exist as a style of equation for atomic and subatomic scale apparently entropic output.)
Knowing that one of the least understood but most significant errors in cryptography would be utterly unknown in any other field of research lends some credence to my thinking that at least some supposedly entropic processes are really pseudoentropic. It's not that I think physics people are "morons", like one person mailed me. By the contrary, they're some of the brightest people around. I just think they're underestimating the degree to which psuedoentropy, defined as a stream of "provably random" data derived from a single seed value, can mask actual entropy. GIGO, and all that.
That being said, that I'm only slightly familiar with the apparently disproved "hidden numbers" theory that believes it directly addresses this line of thought has given me a great deal of humility. My hope is that the argument against hidden numbers tends to focus on easily detectable randomizers and is overapplied to higher level processes.
Both Quantum Intrusion Detection and Quantum Entanglement, of course, make quite a bit of sense with a PRNG in place. Of course two particles can get entangled; if both can be forged with the same seed, they'll vary with exactly matched entropy. (We use this exact property when we use RC4 as an encryption system: By XORing against matched entropy, a sender can transmit to a receiver using what is indistinguishable from pure noise to anyone without the seed value.) But what would the "seed" be? Surely not position and velocity, even if it is tempting to discretize by Planck Length. I nominate direction, defined as degree of relative dimensional translation, but then I don't have much of a place to nominate anything
Whatever the seed value might be, once two particles match in any way, any subsequent measurements of both relative to eachother would tend to be uncomfortably related, even if analyzing each bitstream directly would evidence perfect entropy. And that's what we find from what little I know about the entanglement experiments. (Why yes, I'm throwing doubt on my own words to prevent other people from kooking out on my own gnawing musings.)
As for Quantum Intrusion Detection, a correction that makes perfect sense, the presumption is that it's impossible to duplicate the seed values that give rise to the sender/receiver relationships. But entanglement is all about duplication of seed values, as for that matter is photon transmission through a non-vacuum. You can't hide the fact that states are related by simply saying that entanglement implies "states may change". Spins aren't just changing; they're changing in a manner predictable to one another. If that's possible, it's difficult to out-of-hand conclude that a supposedly intrusion-proof photon couldn't itself be split, and have its entangled partner measured upon the original having its state set. You could claim the newly split pair couldn't possibly have the same seed value -- but that's more of a technological challenge than anything else. Especially if direction is a seed value, four ninety-degree bounces would equalize direction.
There's other stuff on my mind(most notably, some annoyance with the anthropomorphized concept of "observation" and "measurement" that could be abused to presume that the "observation" of dinosaur bones sent a signal sixty-five million years previous to establish the birth and death of dinosaurs in general and that specimen in particular), but I think I'll stop playing public kook for now.
Yours Truly,
Dan Kaminsky
DoxPara Research
http://www.doxpara.com