Reaction to waves

Sun 21 Feb 2016 05:24 PM

I'm late in posting about the discovery of gravity waves, which was announced with much fanfare over a week ago. The New Yorker and the Telegraph have nice write-ups.

The Telegraph headline claims that "this announcement is the scientific highlight of the decade", but everybody said the same thing about the discovery of the Higgs boson. The article written by astronomer Martin Rees acknowledges this. He writes, "This detection is indeed a big deal: one of the great discoveries of the decade - up there with the detection of the Higgs particle, which caused huge razzmatazz two years ago."

I heard Harry Collins give a talk years ago when the LIGO project was just starting, so the news is interesting as an update to that. The positive result occurred earlier than expected, so it's a pleasant surprise for the researchers.

But for someone who hadn't been following the research closely - for me - the result didn't come as a surprise. Theory predicted gravity waves, scientists were persistently refining detectors, and gravity waves were eventually observed. The technical accomplishment and precision is impressive, but the result doesn't pull back the curtain on any cosmic secrets that hadn't been anticipated.

The recent suggestion that there might be a ninth planet out beyond the Kuiper Belt was more of a surprise. And I'm more interested in seeing how the project to observe it turns out. I don't know which result to expect, so I look forward to seeing the evidence accumulate.

Of course, the existence or non-existence of a planet in our solar system is just a local, contingent fact. The existence of the Higgs boson and gravity waves are (perhaps) about the fabric of everything. I suppose that these are billed as the grand discoveries of the decade because of that.

Partly just as a matter of temperament, I'm not dazzled by fundamentality. The theory which predicts the Higgs boson and the theory which predicts gravity waves don't sit too well together.[1] So, despite the observations, we can't simply take both to be confirmed. But if we observe another planet in the outer solar system, it will be a thing which exists. Without fretting about fundamental ontology, planets are things.

[1] For a nice non-technical discussion of this, see this recent article by Lawrence Krauss.