RE: Brace yourselves for gravitational waves
February 12, 2016 at 6:53 am
(This post was last modified: February 12, 2016 at 6:58 am by Alex K.)
(February 12, 2016 at 2:17 am)Thumpalumpacus Wrote:(February 11, 2016 at 5:18 pm)Alex K Wrote: Note also the 10^-21 amplitude. This means that the length of the 4km arms changed by less than 10^-17 meters. That's way smaller than a proton.
Yeah, the news on the radio said 1/1000th the diameter of a proton.
The fact that we can make such a sensitive instrument is, to me, as amazing as the fact that we can detect an occurrence 1.3 billion ly away.
As Freeman Dyson said, "We are the Universe, pondering itself."
Yes, 1/1000 of a proton seems crazy. That corresponds to a resolution rivalling particle colliders, but without investing any energy. The key is (this is my guess) using the uncertainty principle to your advantage by taking a - compared to an LHC collision - extremely long time to do the measurement, by sending lots of coherent laser photons along the same path. This way you get a super precise length measure without having to drain a whole powerplant. still a crass violation of my physics intuition.
The fool hath said in his heart, There is a God. They are corrupt, they have done abominable works, there is none that doeth good.
Psalm 14, KJV revised edition
