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Gravitational wave detectors like LIGO (https://www.ligo.caltech.edu/page/what-is-ligo https://www.ligo.caltech.edu/page/what-is-ligo) are very precise laser ra
by jasonwatkinspdx 9y ago
Gravitational wave detectors like LIGO (https://www.ligo.caltech.edu/page/what-is-ligo https://www.ligo.caltech.edu/page/what-is-ligo) are very precise laser range finders used as rulers. They can measure extremely small expansions and contractions of space itself.
Discovering a quantized theory of gravity is possibly _the_ major open question in physics atm. We presume there's a 'graviton' of some sort, but have not observed it yet.
- peeters 9y agoIf I'm remembering the analogy in the livestream correctly, if you applied the laser's precision to astronomical scales, it would be the equivalent of measuring the distance to the moon with a tolerance the width of a human hair. And in the scales they deal with, a tolerance one-tenth the diameter of a proton.