Gravity Probe B reports its first results at the APS meeting...
...and the winner is: Albert Einstein.
General Relativity is consistent at the 1% level, at least for geodetic precession...
Phew, that was worth the wait.
Frame dragging measurements are still not confirmed due to unexpected systematics, they hope to be able to say something by christmas. 2007.
The GPB home pages have some nasty frame based sub-pages. But the info is there if you just keep clicking.
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Not just unexpected systematics (though that is essentially the reason for the delay); they still plan to correct for the guide star's proper motion using VLBI. (The star is a radio source, so they can really pin it down.) That will buy an order of magnitude or so in precision.
Everett said in his talk that they have some "glimpses" of frame dragging precession, but it's not yet statistically significant. From what I can tell, they have an effect that is of the right magnitude and with the right sign, but is just about hiding in the error bars. So they've got to nail down the systematics and do the VLBI reference frame to nail it totally.
I'm sure they'll see frame dragging consistent with GR
what I worry is that either any GR deviation will be of such low confidence that it will not mean anything, or that it will be exactly consistent with GR but to such low precision that it does not really test any alternatives
I like fundamental tests of physics, but this leaves me a bit cold
"I like fundamental tests of physics, but this leaves me a bit co". Right - one was looking for (even) slight deviations from GR in order to get an idea of where to go with new physics. We'll have to wait for the frame dragging results, but it'll be hard to beat big Al...
changcho