From kfl@access.digex.net Tue Apr 5 01:09:01 EDT 1994 Article: 7638 of comp.theory Path: bigblue.oit.unc.edu!concert!news.duke.edu!MathWorks.Com!europa.eng.gtefsd.com!howland.reston.ans.net!news.intercon.com!news1.digex.net!access.digex.net!not-for-mail From: kfl@access.digex.net (Keith F. Lynch) Newsgroups: comp.theory,sci.physics,sci.math Subject: First quantum parallel computer announced Date: 1 Apr 1994 00:08:11 -0500 Organization: Express Access Public Access UNIX, Greenbelt, Maryland USA Lines: 49 Distribution: inet Message-ID: <2nga7r$ddo@access2.digex.net> NNTP-Posting-Host: access2.digex.net Xref: bigblue.oit.unc.edu comp.theory:7638 sci.physics:61978 sci.math:54597 Here at Northern Virginia University, we've just developed the world's first quantum parallel computer. This makes use of the well known principle of quantum superposition to effectively parallelize a computation as if the one processor was ten to the trillionth power processors or more. As such, we can rapidly compute the solution to a wide range of previously intractable problems. We quickly solved the travelling salesman problem for the 50 state capitals, for instance. We can quickly factor any integer of up to ten to the 12th power digits. We whipped up a program which will, for any mathematical theorem whatsoever, quickly come up with a proof or disproof of less than ten gigabytes, unless there is no proof that short. It comes up, not just with any proof, but with the shortest possible proof. Also, for any "one-way" algorithm (e.g. the one that encrypts password in Unix), it can quickly generate an inverse algorithm suitable for execution on an ordinary computer, unless there is no inverse algorithm of less than ten gigabytes. There are some things we *cannot* do with this setup: * Predict the weather. This requires not just lots of computation, but also arbitrarily precise knowledge of the weather at some previous time. * Construct an encryption scheme which cannot be quickly broken by a similar computer. * Anything which requires arbitrarily large amounts of memory, such as true AI, or such as computing the ten to the trillionth power decimal digit of pi. The hardware we're using consists of an ordinary 486-based PC. We place it in a Schroedinger cat-box, which is what allows the quantum superposition to work. The main difficulty was getting the computer to operate at the cryogenic temperatures necessary for this effect. The effect itself is nothing new. Every lens exhibits it. Light goes every which way at once in any optical system, but light is detectable only at those few places in which it doesn't cancel itself out from arriving out of phase from different directions. But we're the first to demonstrate the effect in an electronic computer. We are looking for new and ingenious applications for this platform. Please reply to this address. -- Keith Lynch, kfl@access.digex.com f p=2,3:2 s q=1 x "f f=3:2 q:f*f>p!'q s q=p#f" w:q p,?$x\8+1*8