Re: Crypto Mini-FAQ

From: Roger Schlafly (rogersc_at_mindspring.com)
Date: 04/30/03 

Date: Wed, 30 Apr 2003 09:28:21 GMT

"Douglas A. Gwyn" <DAGwyn@null.net> wrote
> >>Quantum cryptography has nothing to do with quantum computing...
> > Not much, except that quantum cryptography needs a quantum
> > computer in every repeater and router.
> No! Quantum cryptography merely exploits quantum coherence
> to detect intrusion, or meet some other cryptographic goal.
> "Quantum" *equipment* is required, but that equipment does
> not by any means qualify as quantum computing. The two
> really are quite different.

How do you make a repeater or router without a quantum computer?

> > I don't see much difference. Cold fusion and quantum computing are both
> > just ideas. In both cases, the physics says that it might be possible,
but
> > no
> > one has figured out how to do it. Neither is likely in our lifetimes. If
I
> > had
> > to bet on one or the other, I am not sure which I would pick.
> Cold fusion was obviously a bogus notion in the first place, ...

Maybe some breakthru will make it possible.

> Quantum computing, on the other hand, is not only supported
> by theory, but has been reliably demonstrated in the lab
> (although only on a small scale at present).

I am not convinced of this. There are some quantum mechanics
experiments (such as nuclear magnetic resonance) that have been
repackaged as quantum computing demos, but I don't think
that they have really computed anything, or that they are stepping
stones towards building a quantum computer.

There are various people who have claimed to built a qubit,
and even someone who has claimed to have factored 15 with
qubits, but I don't think that there is even a convincing demo
of 1 qubit. I hope they do, but it seems like it will take some
sort of breakthru.

Relevant Pages

  • Entangled Particle Holographic Optical Nanostorage
    ... Bank Transfer via Quantum Cryptography Based on ... group of Professor Anton Zeilinger, Vienna ... Abwassertechnologien GmbH and Bank Austria -Creditanstalt Today, ... In quantum cryptography, a data key for encoding messages is created ...
    (sci.crypt)
  • Re: interesting article on quantum cryptography
    ... article quantum cryptography works with photons, ... how would a quantum cryptographic scheme work ... logical operations involved in implementing the crypto algorithm. ... Photons are used in implementations because they are much easier to ...
    (sci.crypt)
  • Re: Quantum cryptography tackles video
    ... >>>Physicists at Toshiba have used quantum cryptography to transmit voice ... The key is send via the fiber, as polarized photon pairs, so if A measures ...
    (sci.physics)
  • =?ISO-8859-1?Q?Re=3A_Suche_Vortrag_von_Stephanie_Wehne?= =?ISO-8859-1?Q?r=3A_Quanten
    ... |> An informal introduction to quantum computing and quantum cryptography in particular. ...
    (de.org.ccc)
  • Re: Quantum Cryptography can not work
    ... necessary to somehow route that link. ... You can use an ordinary router. ... confusing quantum cryptography with quantum computing. ... You need a link between the endpoints to send any message including this ...
    (sci.crypt)