A Drone Tour of Louisiana's Massive Gravitational Wave Detector

Gravitational waves, the long-theorized yet never observed carriers of​ the gravitational force, should be among the weakest things in the universe.

Gravity is the fourth fundamental force and a physics outcast; at small scales, it's diminutive, and at quantum scales, it might as well not even exist. It's the force of huge things, growing in accordance with mass and distance. And, while vaporous and weak at small masses and large distances, give it enough mass in a small enough space and it can tear through space-time itself.

It's here, where gravity is at its most extreme, that we might find gravity as waves in the space-time fabric, stretching and distorting, compressing and expanding ever so slightly the cosmic landscape at its largest scales.

But those distortions are really, unimaginably tiny. To make them large enough to be conceivably observable on Earth it will take the most extreme events in the universe: binary star systems involving superdense neutron stars or black holes, or even the Big Bang itself, when the universe was just an infinitesimal wad of, well, everything. (These Big Bang ripples are what was thought to have been observed in 2014's debunked BICEP-2 detec​tion.)

The weakness of these waves, even resulting from such extreme events, is why we need machines lik​e the LIGO detector, which hunts for gravitational waves using interferometry (LIGO stands for Laser Interferometer Gravitational-Wave Observatory). You can see an aerial view of the LIGO detector in Louisiana in this video from Scie​nce magazine.

Fire off some light down two long tubes of precisely equal length and if one beam makes it earlier or later, it may be the result of a space-time distortion. It's tricky.