Re: QC: Shor's algorithm

Anders Sandberg (nv91-asa@nada.kth.se)
Mon, 3 Feb 1997 20:26:27 +0100 (MET)


On Mon, 3 Feb 1997, Mitchell Porter wrote:

> A note for the future: in "Quantum theory of computation and relativistic
> physics" (quant-ph/9701027), Alexander Vlasov (vlasov@physics.harvard.edu)
> writes "... it should be mentioned that in relativistic physics there is
> no sharp division between q-gates and q-states ... This property of a QFT
> has some analogy with functional style of programming in modern computer
> science. In both cases there is no essential difference between data
> (states) and functions (operators). A function can be used as data for
> some other function."

Fascinating! So maybe deep down, everything is Lisp after all...

I have found some bad news: while quantum key exchange is unconditionally
secure, quantum bit comittment, coin-tossing and oblivious transfer are
not unconditionally secure, they can be cracked using EPR and quantum
computers:

Chau, H.F., Lo, H.K. Why quantum bit commitment and ideal quantum coin
tossing are impossible, PhysComp96, quant-ph/9605026
http://babbage.sissa.it/abs/quant-ph/9605026

I found a whole pile of interesting references at quant-ph/9605, a good
month. Mitch, you might be interested in Wang's papers about theory of
general systems; I don't know if they are good, but they looked
interesting.

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