Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Path: utzoo!utgpu!utcsri!utegc!utai!garfield!dalcs!mnetor!uunet!seismo!uwvax!uwmacc!uwmcsd1!uwm-cs!litow From: litow@uwm-cs.UUCP Newsgroups: sci.philosophy.tech Subject: Re: Comment on Superconductivity Message-ID: <650@uwm-cs.UUCP> Date: Tue, 21-Jul-87 10:44:34 EDT Article-I.D.: uwm-cs.650 Posted: Tue Jul 21 10:44:34 1987 Date-Received: Thu, 23-Jul-87 01:06:26 EDT References: <2385@ames.arpa> <8707210421.AA16893@brahms.Berkeley.EDU> Organization: U of Wi-Milw, College of Engineering Lines: 25 Summary: relationship of theory to experiment In article <8707210421.AA16893@brahms.Berkeley.EDU>, obnoxio@BRAHMS.BERKELEY.EDU (Obnoxious Math Grad Student) writes: > Theorists had made speculations about high Tc superconductors long before > they were discovered. But since theory people have such limited imagina- > tions, they need giant hints from nature in order to identify the correct > zeroth order approximation that will kick start their calculations. The above point is very well made. I do not agree that theorists have limited imaginations. I rather thought that 'hints from nature' combined with theoretical calculations,etc. were,taken together,what one generally calls Physics. However,the main contribution in the above paragraph is the idea that significance in a derivation may only be discernable to human intellect after just such a kick start (colorful but useful language) which gets the iteration going so to speak. I would like to extend the observation made by M.Wiener to computer science. In brief his remark explains why I do not accept Church's Thesis. I think that if CT were really the case,then the structure of the physical world would not play a role in computing and vice versa. I am not claiming that physics enters into computing in a first order way. The theorems of computational complexity theory e.g. intractability of Pressburger Theory do not depend upon thermodynamics but the actual scope of our ability to compute may indeed depend upon thermo. I am not speaking of bigger and faster but of conceptual changes caused by our understanding of subtle relations between computing and physics. It is just those 'kick starts' that seem to me to deny that computability is subsumed by Turing machines. I expect that such 'kick starts' will shortly be identified in computer science.