[Phys-L] gravitational wave signal detected

[John Denker <jsd@av8n.com>]

This has been rumored for weeks, but I don't like to spread rumors.
They finally made the official announcement:

  https://www.ligo.caltech.edu/news/ligo20160211

Also:

  https://www.washingtonpost.com/news/speaking-of-science/wp/2016/02/11/cosmic-breakthrough-physicists-detect-gravitational-waves-from-violent-black-hole-merger/

Quoting the Caltech press release:

> For the first time, scientists have observed ripples in the fabric of
> spacetime called gravitational waves, arriving at the earth from a
> cataclysmic event in the distant universe. This confirms a major
> prediction of Albert Einstein’s 1915 general theory of relativity and
> opens an unprecedented new window onto the cosmos.
>
> Gravitational waves carry information about their dramatic origins
> and about the nature of gravity that cannot otherwise be obtained.
> Physicists have concluded that the detected gravitational waves were
> produced during the final fraction of a second of the merger of two
> black holes to produce a single, more massive spinning black hole.
> This collision of two black holes had been predicted but never
> observed.
>
> The gravitational waves were detected on September 14, 2015 at 5:51
> a.m. Eastern Daylight Time (09:51 UTC) by both of the twin Laser
> Interferometer Gravitational-wave Observatory (LIGO) detectors,
> located in Livingston, Louisiana, and Hanford, Washington, USA. The
> LIGO Observatories are funded by the National Science Foundation
> (NSF), and were conceived, built, and are operated by Caltech and
> MIT. The discovery, accepted for publication in the journal Physical
> Review Letters, was made by the LIGO Scientific Collaboration (which
> includes the GEO Collaboration and the Australian Consortium for
> Interferometric Gravitational Astronomy) and the Virgo Collaboration
> using data from the two LIGO detectors.

[snip]