Comments for Quantum Bayesian Networks http://qbnets.wordpress.com Wed, 11 Nov 2009 16:48:19 +0000 http://wordpress.com/ hourly 1 Comment on Useful Quantum Computers Are 200 Years Away by Geordie http://qbnets.wordpress.com/2009/11/10/useful-quantum-computers-wont-be-built-for-another-200-years/#comment-203 Geordie Wed, 11 Nov 2009 16:48:19 +0000 http://qbnets.wordpress.com/?p=1675#comment-203 Hi Bob I can guarantee with 100% certainty that your timing estimate is wrong :) Hi Bob

I can guarantee with 100% certainty that your timing estimate is wrong :)

]]> Comment on The MCMC Revolution by physicsandcake http://qbnets.wordpress.com/2009/10/28/the-mcmc-revolution/#comment-196 physicsandcake Thu, 29 Oct 2009 09:32:31 +0000 http://qbnets.wordpress.com/?p=1542#comment-196 Looks very interesting, thanks. I'll have a read over lunch :) Looks very interesting, thanks. I’ll have a read over lunch :)

]]> Comment on New Quantum Computer Algorithm is So-so by Jack Woehr http://qbnets.wordpress.com/2009/10/19/new-quantum-computer-algorithm-is-so-so/#comment-191 Jack Woehr Sun, 25 Oct 2009 04:44:30 +0000 http://qbnets.wordpress.com/?p=1482#comment-191 I vote for Prof. Moriarty since he is Conan Doyle's Schroedinger's Cat. I vote for Prof. Moriarty since he is Conan Doyle’s Schroedinger’s Cat.

]]> Comment on Quantum Cryptography, Why Do We Fund It? by rrtucci http://qbnets.wordpress.com/2008/10/17/quantum-cryptography-why-do-we-fund-it/#comment-189 rrtucci Thu, 15 Oct 2009 19:36:09 +0000 http://qbnets.wordpress.com/?p=325#comment-189 See also my more recent post: <a href="http://qbnets.wordpress.com/2009/08/29/quantum-internet-snake-oil/" rel="nofollow">Quantum Internet Snake Oil</a> See also my more recent post:

Quantum Internet Snake Oil

]]> Comment on Quantum Cryptography Snake Oil by rrtucci http://qbnets.wordpress.com/2009/06/26/quantum-cryptography-snakeoil/#comment-152 rrtucci Mon, 07 Sep 2009 20:11:20 +0000 http://qbnets.wordpress.com/?p=1016#comment-152 Tae, I disagree with Dan Simon. An area of quantum computing that interests me greatly is the use of a quantum computer to do MCMC. Dan Simon doesn't seem to be aware of very encouraging discoveries that have been made in that area. My objections to quantum crypto are based on an important fact; namely, that there are known classical cryptographic codes that cannot be broken by a quantum computer. Dan Simon's objections to quantum computing seem to be merely his own personal predictions of the future. Tae, I disagree with Dan Simon. An area of quantum computing that interests me greatly is the use of a quantum computer to do MCMC. Dan Simon doesn’t seem to be aware of very encouraging discoveries that have been made in that area. My objections to quantum crypto are based on an important fact; namely, that there are known classical cryptographic codes that cannot be broken by a quantum computer. Dan Simon’s objections to quantum computing seem to be merely his own personal predictions of the future.

]]> Comment on Quantum Cryptography Snake Oil by Tae Song http://qbnets.wordpress.com/2009/06/26/quantum-cryptography-snakeoil/#comment-151 Tae Song Mon, 07 Sep 2009 18:37:55 +0000 http://qbnets.wordpress.com/?p=1016#comment-151 http://www.networkworld.com/weblogs/security/004842.html "Comprehending quantum crypto is not for the weak. It's said not to be quantum computing but is part of quantum mechanics." http://www.educatedguesswork.org/2009/03/dan_simon_on_quantum_crypto.html "Basically, there is one thing that quantum computers have been found to be capable of doing much better than classical computers. That one thing has been characterized variously as "finding hidden subgroups", "solving the abelian stabilizer problem", or "finding periodicities in abelian groups". Because this one thing happens to lead to polynomial-time algorithms for integer factoring and discrete log, quantum computers have been bandied about as an incredible new computing technology, but the truth is that this one thing is really very limited in scope, and in a decade and a half, nobody's found another significant application for it. Moreover, there are lots of (admittedly informal) reasons for believing that quantum computers can't really do anything interesting beyond this one thing. So we're left with a technology that, even if perfected*, is unlikely to be able to accomplish anything of interest beyond solving a certain narrow class of number theory problems.**" http://www.networkworld.com/weblogs/security/004842.html
“Comprehending quantum crypto is not for the weak. It’s said not to be quantum computing but is part of quantum mechanics.”

http://www.educatedguesswork.org/2009/03/dan_simon_on_quantum_crypto.html
“Basically, there is one thing that quantum computers have been found to be capable of doing much better than classical computers. That one thing has been characterized variously as “finding hidden subgroups”, “solving the abelian stabilizer problem”, or “finding periodicities in abelian groups”. Because this one thing happens to lead to polynomial-time algorithms for integer factoring and discrete log, quantum computers have been bandied about as an incredible new computing technology, but the truth is that this one thing is really very limited in scope, and in a decade and a half, nobody’s found another significant application for it.

Moreover, there are lots of (admittedly informal) reasons for believing that quantum computers can’t really do anything interesting beyond this one thing. So we’re left with a technology that, even if perfected*, is unlikely to be able to accomplish anything of interest beyond solving a certain narrow class of number theory problems.**”

]]> Comment on Quantum (Zeno, Anti-Zeno, Hamlet) Effects by rrtucci http://qbnets.wordpress.com/2009/08/25/quantum-zeno-anti-zeno-hamlet-effects/#comment-144 rrtucci Fri, 28 Aug 2009 18:27:47 +0000 http://qbnets.wordpress.com/?p=1247#comment-144 Product of squared cosines. Very true, Chris. Product of squared cosines. Very true, Chris.

]]> Comment on Quantum (Zeno, Anti-Zeno, Hamlet) Effects by Chris B http://qbnets.wordpress.com/2009/08/25/quantum-zeno-anti-zeno-hamlet-effects/#comment-143 Chris B Fri, 28 Aug 2009 14:01:22 +0000 http://qbnets.wordpress.com/?p=1247#comment-143 ... and even if one might be able to perform the measurements in the proposed way, it is clear that the obtained effect is directly introduced by the performed approximations, as what is being calculated/approximated is nothing else than an infinite product of squared cosines(!), which of course cannot diverge. The divergence is just an artefact from the Taylor expansion & the special construction of the time-intervals. I think calculated correctly to product should converge towards 0. The problem with Pankovic's approximation of course is, that the product of the approximations is not an approximation of the product. … and even if one might be able to perform the measurements in the proposed way, it is clear that the obtained effect is directly introduced by the performed approximations, as what is being calculated/approximated is nothing else than an infinite product of squared cosines(!), which of course cannot diverge. The divergence is just an artefact from the Taylor expansion & the special construction of the time-intervals. I think calculated correctly to product should converge towards 0. The problem with Pankovic’s approximation of course is, that the product of the approximations is not an approximation of the product.

]]> Comment on The X-Prize for Quantum Computing, Why Not? by Jack Woehr http://qbnets.wordpress.com/2009/08/23/the-x-prize-for-quantum-computing-why-not/#comment-141 Jack Woehr Mon, 24 Aug 2009 13:35:54 +0000 http://qbnets.wordpress.com/?p=1213#comment-141 No problem, and thanks. Love your idea of an X-Prize. That might stir things up. Went and read the proposer pages, and apparently the app form to propose an X-Prize sort of assumes that the proposer is going to kick in some funding! No problem, and thanks. Love your idea of an X-Prize. That might stir things up. Went and read the proposer pages, and apparently the app form to propose an X-Prize sort of assumes that the proposer is going to kick in some funding!

]]> Comment on The X-Prize for Quantum Computing, Why Not? by rrtucci http://qbnets.wordpress.com/2009/08/23/the-x-prize-for-quantum-computing-why-not/#comment-140 rrtucci Mon, 24 Aug 2009 13:16:52 +0000 http://qbnets.wordpress.com/?p=1213#comment-140 Sorry Jack. I now realize that my intro was "putting words in your mouth". I rewrote the intro of the blog post so as to more clearly separate your opinions from mine. Sorry Jack. I now realize that my intro was “putting words in your mouth”. I rewrote the intro of the blog post so as to more clearly separate your opinions from mine.

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