dgary@ecsvax.UUCP (D Gary Grady) (08/20/85)
The 1985 Aug 10 issue of Science News reports that IBM (of all things!)
has built a 10 gigaFLOP supercomputer specifically to compute the mass
of a proton from quantum chromodynamical "first principles." The
calculation is expected to take a year (!), but would have taken three
centuries (!!!) on a Cray 1.
Now, does anyone remember the name of the guy who wrote in Physics Today
a few years ago that all physicists should go and buy Commodore 64s so
they wouldn't have to use big computers any more?
--
D Gary Grady
Duke U Comp Center, Durham, NC 27706
(919) 684-3695
USENET: {seismo,decvax,ihnp4,akgua,etc.}!mcnc!ecsvax!dgarydgary@ecsvax.UUCP (D Gary Grady) (08/20/85)
The 1985 Aug 10 issue of Science News reports that IBM (!) has developed
a 10 gigaFLOP supercomputer intended specifically to compute the mass of
a proton from quantum chromodynamical "first principles." The
calculation is expected to require 1 year (!!), but would have taken
three centuries on a Cray 1 (!!!). After it's done, it can be put to
other, similar uses.
--
D Gary Grady
Duke U Comp Center, Durham, NC 27706
(919) 684-3695
USENET: {seismo,decvax,ihnp4,akgua,etc.}!mcnc!ecsvax!dgarysra@oddjob.UUCP (Scott R. Anderson) (08/23/85)
In article <278@ecsvax.UUCP> dgary@ecsvax.UUCP (D Gary Grady) writes: >The 1985 Aug 10 issue of Science News reports that IBM (of all things!) >has built a 10 gigaFLOP supercomputer specifically to compute the mass >of a proton from quantum chromodynamical "first principles." The >calculation is expected to take a year (!), but would have taken three >centuries (!!!) on a Cray 1. > >Now, does anyone remember the name of the guy who wrote in Physics Today >a few years ago that all physicists should go and buy Commodore 64s so >they wouldn't have to use big computers any more? >-- The author's name is Per Bak, and his point was that many of the calculations that physicists used to do on mainframes can now be done on home computers. That doesn't mean that there aren't calculations that need to be done on large computers. Scott Anderson ihnp4!oddjob!kaos!sra Project: Get a Cray-1 for my living room.
dgary@ecsvax.UUCP (D Gary Grady) (08/26/85)
In article <939@oddjob.UUCP> sra@kaos (Scott Anderson) writes: > In article <278@ecsvax.UUCP> dgary@ecsvax.UUCP (D Gary Grady) writes: > [...] > >Now, does anyone remember the name of the guy who wrote in Physics Today > >a few years ago that all physicists should go and buy Commodore 64s so > >they wouldn't have to use big computers any more? > > The author's name is Per Bak, and his point was that many of the calculations > that physicists used to do on mainframes can now be done on home computers. > That doesn't mean that there aren't calculations that need to be done on > large computers. I was only kidding (sorry about the missing :=) ), but it's worth noting that Bak's article was a little overly enthusiastic, if I'm remembering it correctly. I don't fault him for pointing out the utility of micros for scientific use, but at the same time it's important to note that there were, at the time the article was written, serious objections to using them for serious scientific work. The main problem was software, including compilers and subroutine libraries. Many BASIC interpreters (and I believe Bak specifically gave examples of programs in BASIC) have poorly written scientific functions, for example, which give little if any accuracy in parts of their domains. An article in Scientific American compared the accuracy of various compilers and interpreters on micros and mainframes, with most of them making an unimpressive showing compared with a pocket calculator. Unfortunately, many scientists are self-taught computerists and either don't know enough to worry about such problems or are inclined to think it "won't happen to them" in the fine tradition of seat belt usage. If you think I'm overly pessimistic, think about how many of your colleagues use IBM's SSP (including, ghu help us, RANDU). Have YOU ever checked out the claimed accuracy of your library functions? -- D Gary Grady Duke U Comp Center, Durham, NC 27706 (919) 684-3695 USENET: {seismo,decvax,ihnp4,akgua,etc.}!mcnc!ecsvax!dgary
sra@oddjob.UUCP (Scott R. Anderson) (08/28/85)
Somewhere in net.physics, D Gary Grady writes: >> >Now, does anyone remember the name of the guy who wrote in Physics Today >> >a few years ago that all physicists should go and buy Commodore 64s so >> >they wouldn't have to use big computers any more? >> >I was only kidding (sorry about the missing :=) ), but it's worth noting >that Bak's article was a little overly enthusiastic, if I'm remembering >it correctly. I have to agree that it was somewhat "overly enthusiastic"; I took exception (over-enthusiastically? (:-) because I use Sun Workstations in much the same way that Per Bak used his Commodore, although not at home (I wish!). For most of my work, they are very adequate. >The main problem was software, including compilers and subroutine >libraries. Many BASIC interpreters (and I believe Bak specifically gave >examples of programs in BASIC) have poorly written scientific functions, >for example, which give little if any accuracy in parts of their domains. Using BASIC was his biggest mistake! I don't believe that any part of his program used scientific functions, though. Can I trust a Commodore 64's floating point software? >Unfortunately, many scientists are self-taught computerists Like me (:-). >and either don't know enough to worry about such problems or are >inclined to think it "won't happen to them" in the fine tradition of >seat belt usage. It isn't just scientists, but also engineers, business people, etc.,... I guess this is a case of shoddy American worksmanship and "caveat emptor" (:-). >If you think I'm overly pessimistic, think about how >many of your colleagues use IBM's SSP (including, ghu help us, RANDU). The people around here stay as far away from IBM computers as possible (unless they are given to them. (:-) >Have YOU ever checked out the claimed accuracy of your library >functions? Not the math functions. We run 4.2BSD; can anybody tell me which of these routines have limitations and what they are? I don't recall even *seeing* any claims of accuracy. The random number generators are another story. I quickly discovered that rand() is useless. However, did you know that even random() generates an incorrect second moment? (Details on request.) I am currently using the generator referenced in Bak's article, and have found it to be better than both of these, and to be of intermediate speed. >An article in Scientific American compared the accuracy of >various compilers and interpreters on micros and mainframes, with most >of them making an unimpressive showing compared with a pocket >calculator. Can someone give me a reference for this article? Also, can anyone give me any references for writing mathematical function subroutines? Scott Anderson ihnp4!oddjob!kaos!sra