Why did they not do these computations in Mathematica. Once one defines a framework (program) in Mathematica to do long and complex calculations, and you test it with known good data to ensure it is correct, you are virtually guaranteed to find the correct answer with real data. Many of the real gains in astrophysics and in developments of the atomic bomb after the Second World War were done on Macsyma, a forerunner of today's computer algebra systems. Mathematica really is a Godsend if you must have the correct answers to long and difficult problems.
Charles Elliott > -----Original Message----- > From: [email protected] > [mailto:[email protected]] On > Behalf Of Danny Mayer > Sent: Tuesday, December 27, 2011 11:36 PM > To: Greg Hennessy > Cc: [email protected] > Subject: Re: [ntp:questions] Accuracy of NTP - Advice Needed > > On 12/27/2011 10:39 PM, Greg Hennessy wrote: > >>> The bottom line is that the only thing that is relevant is how easy > it is > >>> to get to a GPS antenna with an open view of the sky. > >>> > >>> Everything else is bloviation. > >> > >> GPS is not used for this kind of thing, they are too inaccurate, so > it > >> doesn't matter. They use atomic clocks. > > > > GPS is indeed used for the measurement of the time of flight in the > > CERN and Fermilab experiments. You should read the papers. They use > > GPS to get time to the order of nanosecond accuracy. > > > > You can read some of this here: > http://www.wired.com/wiredscience/2011/09/scientists-question- > neutrinos/ > > It's not too technical but describes the basic setup. Yes they did use > GPS to get accurate locations of the equipment but it's a rather > complex > and hard to get right. They then used Cesium atomic clocks for timing > the events. The calculations you have to do for all this is > mind-boggling and there is a lot of work that has to go into ensuring > that they are accurate and nothing got missed. That's the principle > reason that it's hard to be sure that an FTL result was obtained. There > are lots of scientists pouring over calculations (there were something > like 150 authors listed on the paper published in arXiv. Hords of other > scientists are also analyzing the data. > > Danny > _______________________________________________ > questions mailing list > [email protected] > http://lists.ntp.org/listinfo/questions _______________________________________________ questions mailing list [email protected] http://lists.ntp.org/listinfo/questions
