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Dark Matter Identified?

06/23/2016 1:35 PM

Did the gravitational wave detector also detect dark matter? Read this and find out.

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#1

Re: Dark Matter Identified?

06/23/2016 1:59 PM

That is some very interesting reading. Thank You.

The reporter in making this synopsis inadvertently made a critical ambiguity for me. (I could also be my misreading. ) Are the 36 and 29 solar mass black holes the two colliding holes from the first LIGO detection or the combined mass for the first and second detection by LIGO?

Regardless, this very well might be the first detection of Dark Matter.

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#3
In reply to #1

Re: Dark Matter Identified?

06/23/2016 2:41 PM

36 and 29 were the masses of the two black holes that merged in the September detection (1st detection). In the latest detection in June, the masses were 14.2 and 7.5 solar masses. The first resulted in a hole of 62 solar masses with 3 solar masses converted to energy. The second resulted in a hole of 20.8 solar masses with 1 solar mass radiated away.

https://en.wikipedia.org/wiki/Gravitational_wave

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#5
In reply to #3

Re: Dark Matter Identified?

06/23/2016 9:51 PM

Let me get this straight.

In the first detection, the mass of 65 of our suns in the mutual form of two black holes came together to form one black hole with a mass of 62 of our suns. The missing 3 suns worth of mass in this one event was converted to energy (light). With all of these things already being black holes, all of this transmutation to energy happened within some event horizon. With the plausible exception of any matter about to hurtle into these holes at this moment, none of the enormous energy left the new hole. The loss of the gravitational field from this now missing matter is what rippled space-time for LIGO to detect.

DANG!!!!

This makes me want to get back into a Physics program.

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#6
In reply to #5

Re: Dark Matter Identified?

06/23/2016 10:16 PM

The missing 3 suns worth of mass in this one event was converted to energy (light).

Actually, according to the article, 3 suns worth of mass was converted to gravitational waves 1.3 billion years ago last September 14th.

https://en.wikipedia.org/wiki/Gravitational_wave:

"LIGO observations[edit]

LIGO measurement of the gravitational waves at the Hanford (left) and Livingston (right) detectors, compared to the theoretical predicted values. Main article: First observation of gravitational waves

On 11 February 2016, the LIGOcollaboration announced thedetection of gravitational waves, from a signal detected at 09:50:45 GMT on 14 September 2015[65] of two black holes with masses of 29 and 36 solar masses merging about 1.3 billion light years away. During the final fraction of a second of the merger, it released more than 50 times the power of all the stars in the observable universe combined.[66] The signal increased in frequency from 35 to 250 Hz over 10 cycles (5 orbits) as it rose in strength for a period of 0.2 second.[9] The mass of the new merged black hole was 62 solar masses. Energy equivalent to three solar masses was emitted as gravitational waves.[67] The signal was seen by both LIGO detectors in Livingston and Hanford, with a time difference of 7 milliseconds due to the angle between the two detectors and the source. The signal came from the Southern Celestial Hemisphere, in the rough direction of (but much further away than) the Magellanic Clouds.[8] The confidence level of this being an observation of gravitational waves was 99.99994%.[67]

On 15 June 2016, the LIGO group announced the detection of a second set of gravitational waves, which was observed at 03:38:53 GMT on 26 December 2015. The signal was seen by the Hanford LIGO detector 1.1 milliseconds after the Livingston detector. The signal rose from 35 to 450 Hz over the course of 55 cycles (27 orbits) during the period of observation of about a second. Analysis of the signal indicates that this event represented the merger of two black holes about 1.4 billion light years distant, with masses of about 14.2 and 7.5 solar masses, yielding a combined black hole of approximately of 20.8 solar masses, with one solar mass radiated away. The estimated spin parameter (ratio of angular momentum to theoretical limit) of the final black hole is 0.74, slightly higher than for the first detection (0.67); it was also found that at least one of the premerger black holes had a spin of greater than 0.2. This measurement provided additional support for general relativity.[11][12]"

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#2

Re: Dark Matter Identified?

06/23/2016 2:00 PM

The mass of the matter times the square of the lair equals the invisibility of the darkness....Yes seems to add up...

Could we ask Steven to make an episode....?

http://www.pbs.org/show/genius-stephen-hawking/

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#4

Re: Dark Matter Identified?

06/23/2016 6:49 PM

It shows there are black holes out there, primordial black holes, that are too big to be collapsed stars and too small to be galactic cores. Primordial black holes are one of the candidates for the dark matter.

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#7

Re: Dark Matter Identified?

06/24/2016 2:24 AM

TLDR version is that they did?

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#8
In reply to #7

Re: Dark Matter Identified?

06/24/2016 7:09 AM

Too Long Didn't Read?

To eschew obfuscation one should define abbreviations.

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#9
In reply to #8

Re: Dark Matter Identified?

06/24/2016 7:38 AM

Since when is TLDR not Too Long Didn't Read?

But yeah I meant that

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