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Comment Re:They've already busted that twice now (Score 2, Interesting) 795

Well, maybe he's bringing along one of our prototype military lasers! There are solid-state 100Kw lasers in test that I'm sure will sink a wooden ship just fine...!

"Kids, remember to study math and science. Because math and science will let you build LASER CANNONS to BLOW #$% UP!"

Comment Re:On The Practical Side (Score 1) 467

No, no, no. For this, use a one-time pad.

What you do is this:

Take your file (A). Generate a block of high-entropy random data (B).

Now generate (A xor B), and throw away A. You now have two random files, B and (A xor B), and B xor (A xor B) will give you A again.

A cute variant: instead of generating a really random B, use pseudo-random data generated from a known key (mp3 rip of some song of a particular version of a CD, gzip of linux kernel source), and don't even keep B with you; regenerate it on the other side. There are lots of ways to screw this trick up, though, so consult a cryptographer.

You could use more than 2 files if you want, the idea is basically the same.

Comment Re:Is this chip a bargin? (Score 1) 292

A lot less; it's not a coincidence that IBM never publishes any industry-standard benchmarks on these things.

Don't get me wrong; they're fast, but they're not magic, and they're not remotely competitive on a price/raw-compute-cycle basis. If that's what you want go get a beowulf cluster.

Comment Re:What would the impacts of this be for cryptogra (Score 0) 457

Short form:if P=NP, crypto is something of a futile effort - that implies that there's a non-brute-force crack to every possible private-key algorythm. I suppose it might still be slow enough for the crypto to be useful, but I woudl expect you would end up needing gigantic keys.

Most everybody assumed that P!=NP, but nobody has been able to prove it.

You will lose an important tape file.