Gravitational Wave Detector Finds Double Colliding Black Holes — Again (Woot!)

Distortions in the fabric of space-time, which were predicted by Albert Einstein a century ago, have been directly detected for the second time.

Approximately 1.4 billion light-years from Earth, two black holes spiraled around each other and collided, creating ripples in the fabric of space-time. These ripples, known as gravitational waves, arrived at Earth in December 2015, and were detected by the Laser Interferometer Gravitational Wave Observatory (LIGO).

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Again? I had a look at the original data and there was sign of a second. What is the date of this second one?

There’s been a recent (June 2016) technical paper refining the masses and interactions of the first detected black hole collision. For instance, the redshift of the source galaxy has a very significant influence on the calculated masses.

http://www.sciencealert.com/physicists-say-we-might-have-found-dark-matter-while-detecting-gravitational-waves

From CN’s link
“This graph shows the gravitational wave signal detected by LIGO on in December of 2016.”

I assume they meant to say “December 2015”. It’s not a particularly strong signal, pretty close to the limits of detectability. The first GW found was a very strong signal, perhaps 100 or 1000 times as powerful as the new one.

From CE’s link
“We are not proposing this is the dark matter. It’s a plausibility argument.”

I can live with that.

Dark Matter May Be Made of Primordial Black Holes

Postpocelipse said:

Dark Matter May Be Made of Primordial Black Holes

Nice site.