[ExI] A Working Quantum Computer by 2017?

spike spike66 at att.net
Mon Sep 5 00:24:24 UTC 2016



From: extropy-chat [mailto:extropy-chat-bounces at lists.extropy.org] On Behalf Of William Flynn Wallace
Sent: Sunday, September 04, 2016 4:06 PM
To: ExI chat list <extropy-chat at lists.extropy.org>
Subject: Re: [ExI] A Working Quantum Computer by 2017?


But the ones we care most about tend to be simulations, and this is where quantum computers could shine.   anders


>…  what, if any, ways are there to validate simulations?  Well, let the world go by and see what really happens, I suppose.  What else?  Do real world experiments?  In short, why trust simulations?   …bill w



BillW, the way I saw sims develop in real world engineering is that it guided design.  We used Matlab and Simulink, worked a configuration on the computer, got it working where we wanted by swapping in and out components we had at our disposal, found out the combinations of stuff that would do what we wanted.


Then, we went into the lab and built what we had simulated.  Those sims were seldom off by much.


A more startling example happened in the earlier days, in about 1993.  We had a missile with a two-piece aero-shroud that would peel away like a clamshell and fall away at about 70 kft where the air was thin.  It was instrumented and we wanted to recover the two pieces but couldn’t have it transmit and couldn’t have much of a power source for a pinger.  We didn’t want the shroud to fall anywhere off the range (White Sands) where we wouldn’t necessarily have access to it, and of couse we didn’t want it coming down and conking some local prole or his cow.  So… we calculated where we expected them to fall and created a classic circle of equal probability (in this case an ellipse (actually two of them because the two pieces were slightly different shapes and masses)) using only closed-form equations and no computers at all.


We formed two teams: our team was two PhDs in aerodynamics and I was the junior guy who ground through the equations by hand (they wrote em, I solved them, then they checked the result (I was the one who went home smelling like sweat at the end of the day.))


The other team were these two guys even younger than I, in their 20s, didn’t even have engineering degrees (they were technologist who knew sims)  The two were contractors with their own company.  They came in, created wire-frame digital models, ran a jillion sims, drew an ellipse that enclosed half their simulated landing spots, done.  The docs and I took about three weeks.  The two younger fellers finished a good couple days before us with smaller ellipses, inside ours.  Eeeeverybody was quietly watching this whole experiment, because I had to report there was some risk of one of the shroud pieces landing off the range, but the other guys suggested the risk was much smaller.


The test firing happened, both pieces fell within their ellipse.


That was a wakeup call.  I took up Simulink and Matlab with renewed vigor.







-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.extropy.org/pipermail/extropy-chat/attachments/20160904/8bd7f495/attachment.html>

More information about the extropy-chat mailing list