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Message: <blockquote data-quote="freyar" data-source="post: 6797150" data-attributes="member: 40227">Oh, of course, everyone wanted to see something different than the Standard Model Higgs from the LHC (and there are hints we may get something else this summer).  But comparing the Higgs search to this experiment is not an apples-to-apples comparison.  There were very good reasons to do the Higgs search --- for mathematical reasons, something had to show up in the energy range that the LHC reached with very high certainty, and even a failed search would have told us a lot.  There also are/were very good reasons to expect the LHC to find something other than or in addition to the Standard Model Higgs, at least if you include the 2nd run (which is going on right now).  And, again, finding just the Standard Model Higgs would also have told us a lot.  Another, extremely important issue, is that the LHC was feasible --- expensive, certainly, and non-trivial, but feasible.  On the other hand, just because someone has now calculated the metric in the presence of a solenoid with large field does not provide great justification for building an entire LIGO detector just for that (I might mention that, with the very weak gravitational effects of even the 20 Tesla field mentioned in the experiment design, you really only need the perturbative calculation, which I think the paper said had been done before).  Furthermore, we're talking about trying to keep the light wave in the detector coherent for 200 days (very challenging) to have a hope of seeing a signal, and that's before talking about noise.  Now, a gravitational wave experiment like LIGO has to "hear" a signal through lots of noise --- things like very tiny seismic rumbles, etc, etc.  But LIGO's gravitational wave signals would be detected over seconds or minutes.  If you have add those over 200 days, that'll be a bigger background.  And gravitational waves will be backgrounds, too.  I'd worry there's an irreducible background, and I'd also worry that the situation is much worse, since I'm a theorist and don't know half the trouble that goes into these things.  The other thing is that there is no reason theoretically to think there could be a big pay off from this experiment.  We understand weak field gravity very well, so weak field quantum gravity is very constrained by what we know already.  My feeling, which is borne out by the fact that no one in the physics community seems to have paid any attention to this proposal 8 or 9 months after it first came out, is that people don't find this to be very promising.  That's all.  Maybe someday, if we're able to produce much bigger magnetic fields, someone will follow up on this.  But I do suspect we'll have better ways to test quantum gravity by then, too.</blockquote>

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