Monday, 30 April 2007

James Hartle about Gravity

Last week CERN enjoyed a visit of James Hartle, the Hartle in the Hartle-Hawking wavefunction. James gave a theory seminar on which i will share some remarks another time. He also gave a general audience colloqium entitled The Future of Gravity. This one i'm reporting in passing, as there is not much to report on. The colloqium was a piece about past and future tests of Einstein's general relativity.
It was a standard Google talk. It seems as if James googled for "test" , "Einstein", "gravity". The results returned by the search engine were spanning the whole spectrum of experimental efforts, from the laboratory and solar system studies of weak-field gravity, to observations of strong-gravity phenomena in astrophysical environments. One hour of pictures&names and little infortmation. Not that it was a total waste of time. The subject itself is fascinating enough, with the tremendous experimental progress going on. However, one would expect more than just hopping from one experiment to another.

Neither video nor transparencies from the CERN colloqium are available. If you're not disencouraged yet, here you can find transparencies from a somewhat similar talk given in Santa Barbara.

7 comments:

Anonymous said...

"standard Google talk" is a good one. I think you just coined an instant classic!

ofer said...

Did he point any discrepancy with GR? Did he mention the Pioneer anomalous shift?

Anonymous said...

Is it not funny that there is no record
kept of past talks from the CERN theory group except this blog? Who knows, one might find in the transparencies more stuff than the limited second hand information passed in here.

It is rather sad that the very popular, very easy, very useful, and very much CERN-developed tool (agenda.cern.ch)
for cataloging seminar series, meetings
and conferences is not known to the
theory group

Jester said...

Ofer, there was no mention of the Pioneer anomaly. And that's fine. I also wouldn't count it as a discrepancy with GR.

ofer said...

jester,
perhaps ``discrepancy'' is too strong, but how would you classify a decade-persistent anomalous shift in the trajectory of two spacecrafts embedded in a weak gravitational field?

Jester said...

ofer, i believe in the RTGs as an explanation. I think in this case Ockham's razor is particularly sharp.

ofer said...

jester, perhaps you are right. Yet, the LHC is orders of magnitude more complex than two spacecrafts. And still, if the machine will produce the SM + an additional unexpected (but persistent) signal, then the possibility of new physics won't be ruled out just because the signal is more likley to come from a bug in the software or hardware defects...