In praise of theoretical science


I’m thrilled, I truly am, that they’ve detected those gravitational waves but I’m also a little upset. You see, that used to be the one serious, impressive-sounding and reasonably topical scientific topic I could hold an intelligent conversation about for at least two minutes. Now, anybody can be sufficiently expert for the purposes of showing off at a cocktail party. All they need do is read a few articles and click a couple of animated videos showing how gravitational waves ripple through, warp, distort or deform space-time (a fine variety of verbs seems to have been used) or what the coalescence of two black holes looks and sounds like. Actually, I’m curious about that, what “sound” did we exactly hear? Surely it’s some kind of projection of data into sound rather than a faint billion-year old “pop”?


The reason I had some idea of “what it’s all about, anyway?” is that I am lucky enough to have worked for seven years in a research centre, IHES, which focuses 100% on theoretical research. One day, I was volunteered to write a short article about what some IHES researchers were doing on gravitational waves for a newsletter. This was a task I was very happy to oblige with, because Thibault Damour had agreed to give me a one-to-one explanation. Professor Damour is a theoretical physicist and a leading light on all things to do with Einstein’s general relativity theory, cosmology and what we may now call gravitational astronomy because, guess what, they created a new science yesterday.

The way I understand it, Thibault Damour, and the many people who work and have worked with him, have been instrumental in providing one of the four keys that helped us unlock the actual physical detection of gravitational waves. The first one was provided by Einstein’s prediction, a century ago. The second is the mathematical constructions needed to guide detectors on where to focus their efforts, a major challenge being to filter out all the “white noise” for want of a better word. That is essentially Thibault Damour’s work, as I understand it. (Incidentally, I find it amusing that he worked some twenty years ago on this with an Italian born researcher whose first name is Alessandra* and currently works on this with an Italian researcher whose first name is Alessandro**.) The third key is of course the building of these amazing interferometers. I remember Alessandro telling me that when gravitational waves were finally detected, the powers that be would surely release the funds to build them on a massive scale to get better information, in space no less; I wonder if he will be proved right? And the fourth key  was the data crunching provided by the numerical simulations, which were closely linked to the mathematical modelling.

Yes, this project really was team work. An international team, obviously, with people who have been making their contribution to this tremendous leap in human knowledge.



** Nagar (a talented cartoonist as well as a physicist)