(This piece originally appeared in the “Will we ever?” column at BBC Future. Though I added a few visuals, I left the UK spellings and BBC stylebook conventions in place.)
One portion of the LIGO gravitational wave detector, located in Louisiana. [Credit: moi]Gravity affects the shape of space and time. Paths of light and massive bodies curve under its influence. When something churns space-time with enough energy – say a supernova explosion or two black holes in orbit around each other – the distortion spreads out in ripples, like a rock dropped in a pond. Those ripples are called gravitational waves. These are very weak but, if the accelerating object has enough mass, it should be possible to spot them.
At least, that’s what we suspect. Gravitational waves were predicted by Einstein’s general theory of relativity in 1916, and we’ve been trying to detect them ever since.
While we’ve never measured these waves directly, we have lots of indirect evidence. In 1974, student Russell Hulse and his supervisor Joseph Taylor calculated that a pair of burnt-out stars spiralling towards one another were radiating gravitational waves at exactly the rate predicted by Einstein. This earned both researchers a Nobel prize around ...