I look forward to your solution for the key distribution problem. If you have a secure channel to convey a secret key of n bits, why not just use the channel it to convey the secret message it would otherwise encrypt?

]]>Good look for everyone ]]>

“Lord Kelvin (1895) missed birds? Seems hard to believe…”

We are talking Victorian Britain, where Charles Darwin was to frightened to publish his ideas on evolution due to what we now call the “creationist” view point being the dominant one. Where science and politics trod timidly in the shadow of the Church.

Being a presbyterian his viewpoint would probably have been “birds are creatures of God” and “machines the work of man”, and the two where incomparable due to their respective creators.

As a matter of historical fact man had made several “heavier than air” machines that had flown as well as the “lighter than air” baloons etc, prior to Lord Kelvin’s (William Thomson) pronouncment.

He even repeated his pronouncment in 1902 saying he doubted they would be of practical significance. This was just five years prior to his death and as we now know within a decade of areoplanes becoming practical and shortly there after changing the face of war forever.

This was not the first time William Thomson had made an incorrect pronouncment, he originaly pronounced X-rays to be impossible. And just a short while later had it proved to him as well as later having his hand X-rayed.

These pronouncments from a man so venerable as to be considered the “father of physics” might well have been the thing that prompted the Arther C Clark comment 😉

]]>Lord Kelvin (1895) missed birds? Seems hard to believe… ]]>

“That they somehow manage an end-run around the Church-Turing Thesis?”

it may be closer than you think…..

]]>Computability has nothing to do with complexity.

Clearly factoring is computable….What we are talking has nothing to do with computable or not.

As for complexity.. Here is an example with optical computers. I have a problem that runs in O(n (n ln n )) time since i need to do on the order of n FFT/IFFTs. Optical computers (in a fancy way) can do the FT in constant time when built that way. So now the complexity goes down to O(n) rather than O(n^2 ln n). If n is big this can be quite a speed up.

The same thing can be said for normal complexity on plain computers. Assumptions mater. Many O() results may only count arithmetic operations, while these days getting a number from memory can in fact be much slower. Also what is n. Factoring with \rho factorization is O(sqrt(n)) IIRC. But that where n is the number — not the number of digits that cryptographers may use, in this case it becomes O(exp(n)).

I could go on. Also as i said before we don’t even know if factorization is in P or not.

Anyway the wiki entry… not always the most accurate info, but a good place to start.

http://en.wikipedia.org/wiki/Quantum_computer#Relation_to_computational_complexity_theory

http://en.wikipedia.org/wiki/BQP

Did someone claim to have a quantum computing algorithm for the Busy Beaver problem? Complexity is not computability.

]]>“Now all your sinners

This is the prophecy

The revelations of your own destiny

Sleep well and dream on

The dream that you have sold

And now my brothers

This world is slowly getting cold…”

LOL!

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