Another Einstein prediction verified...

[gzhpcu]

http://www.wired.com/wiredscience/20...+International

Four superconducting ping-pong balls floating in space have just confirmed two key predictions of Einstein’s general relativity, physicists announced in a press conference May 4.

[wd40]

What would have been the implication if Einstein's prediction had not been verified and the deviation not measured?

Would it have been a major blow against Relativity? Or could a work-around have been formulated?









"If Michelson-Morley is wrong, then Relativity is wrong" (Albert Einstein)

[Perikles]

Thanks - that is really interesting. Incredible to think that it was not that long ago when Einstein said

“their magnitude is so small that confirmation of them by lab experiments is not to be thought of.”

[Grey]

What would have been the implication if Einstein's prediction had not been verified and the deviation not measured?

Would it have been a major blow against Relativity? Or could a work-around have been formulated?

General relativity is astonishingly good at making accurate predictions in its domain. And as we see here with Gravity Probe B, those predictions are being measured to a remarkable level of precision. So any future replacement to it will have to essentially reduce to making the same predictions as general relativity in all the cases we've been able to test so far, just as general relativity itself reduces to Newtonian mechanics in most cases. Even today we still teach classical mechanics and electrodynamics to students learning physics before we start in on relativity and quantum theory. I suspect that even if someday we find a discrepancy between general relativity and experiment that requires us to modify or replace relativity, we'll still teach it, and probably continue to use it for the intermediate cases where Newtonian gravity isn't quite precise enough, but we don't need a full treatment of neo-hyper-relativistic gravity (or whatever).

There have been a number of competitors to Einstein's general relativity that still start with the basic premise of the equivalence principle, but differ in a few of the particulars. They're all pretty similar to general relativity, so using one of those models instead wouldn't really upset physics significantly. So far, to my knowledge, all of them either make the same predictions as general relativity for all measurements made so far, or they've been ruled out by experiment. The results from Gravity Probe B might rule out a few more of them; I'm not sure.

[NEOWatcher]

What would have been the implication if Einstein's prediction had not been verified and the deviation not measured?
Would it have been a major blow against Relativity? Or could a work-around have been formulated?

It depends on whether they could determine the issue with the experiment. There doesn't need to be a work around, just an analysis of what the difference between experiment and prediction. Odds are that it would just be a failed experiment.

I once heard a quote by some chemistry teacher (I think) something to the tone of "I can't tell you the exact outcome of your experiment, but I can explain what was behind your outcome".