Wednesday, 19 January 2022

You'll shoot your eye out: the shock of the recoil

The latest data dump from gravitational-wave detectors turns out to be full of juicy science, just waiting to be scooped out. 

Last month it was the first measurement of black holes enacting one of the most gorgeous quirks of Einstein's famously peculiar theory of gravity. Two black holes were spiralling into each other and one of them was spinning almost as fast as physically possible and that, through a process with no analogue in our daily experience, caused the entire orbit to affect a gentle sway. The effect was ten billion times stronger than previous measurements, which were from much less extreme events, by which I mean two stars that have been squashed to only ten kilometres across and are orbiting each other ten times closer than Mercury orbits our sun, and are therefore rather pedestrian compared to black holes colliding.

This month came a new wonder from the same event: after the two black holes merged into one, the final massive black hole -- over sixty times more massive than the sun -- received a huge kick from the gravitational waves it gave off and shot away across space at over 700km per second. At least! It was more likely 1500km per second, and could have been as high as 2500. Ok, these are all extreme crazy astronomical things, everything goes fast. Is that really such a big deal? Yes! If this merger happened deep in the obscure innards of some galaxy, the final black hole would be hurtling fast enough to escape the galaxy and zoom off into empty space. 

Wednesday, 22 December 2021

Breaking news! Scientists measure an exciting phenomena you have never heard of!

I. When black holes wobble

Precession! We have finally observed precession in gravitational waves!

I'm told there are several people in the world who do not feel a wild thrill of joy at those words. There are people who have not been breathlessly waiting for this moment for over five years. There are even people -- it's difficult to believe, but I will trust my sources -- who don't know what the hell I'm talking about. 

Sunday, 7 March 2021

The Which Hunter

Here follows the story of my adventures with an obscure rule of English usage. Brace yourself.

The story begins in my first year of graduate school at the University of North Carolina at Chapel Hill. One of the emeritus faculty was Eugen Merzbacher. Many years previously he wrote what became a standard quantum mechanics textbook. It was so ubiquitous that when one of my fellow PhD students visited the university before accepting their offer of a place in the graduate program, he was utterly starstruck to discover that he would be hosted at Merzbacher's house. He breathlessly recalled his time in the home of the maestro. "I couldn't believe it! In the morning Merzbacher cooked me eggs!"