LIGO Team Report Direct Detection of Gravitational Waves

Morbert

http://news.mit.edu/2016/ligo-first-detection-gravitational-waves-0211

Physical Review Letters website is down so I can't directly link to the paper. When it's back up I'll provide a link and a brief summary.

Another good writeup:

"Scientists Spot the Garvity Waves that Flex the Universe"
http://www.wired.com/2016/02/scientists-spot-the-gravity-waves-that-flex-the-universe/

[edit]- Here's the PRL paper. http://journals.aps.org/prl/abstract/10.1103/PhysRevLett.116.061102#fulltext

Protip: When reading scientific papers, it's best to read the abstract first, then the conclusion, then the figures and captions.

Fig 2 in particular shows the relationship between the signature detected by LIGO and the physical stages of merging black holes.


Fig 3 Is a basic explanation of how LIGO works. Laser beams shining through different arms of the apparatus shift their interference patterns as gravitational waves stretch and contract those arms.


Note that the gravitational wave strain is given by the equation

[latex]\delta L_x - \delta L_y = h(t) L[/latex]

It is on the order of 10^-21, and the arm lengths are 4km, which means (If I did the math right) the arms were shifting by about one ten-trillionth of the width of a human hair.

[edit2] - Fixed back-of the envelope estimate above

Anonymo

Morbert wrote: »

http://news.mit.edu/2016/ligo-first-detection-gravitational-waves-0211

Physical Review Letters website is down so I can't directly link to the paper. When it's back up I'll provide a link and a brief summary.

Another good writeup:

"Scientists Spot the Garvity Waves that Flex the Universe"
http://www.wired.com/2016/02/scientists-spot-the-gravity-waves-that-flex-the-universe/

[edit]- Here's the PRL paper. http://journals.aps.org/prl/abstract/10.1103/PhysRevLett.116.061102#fulltext

Protip: When reading scientific papers, it's best to read the abstract first, then the conclusion, then the figures and captions.

Fig 2 in particular shows the relationship between the signature detected by LIGO and the physical stages of merging black holes.


Fig 3 Is a basic explanation of how LIGO works. Laser beams shining through different arms of the apparatus shift their interference patterns as gravitational waves stretch and contract those arms.


Note that the gravitational wave strain is given by the equation

[latex]\delta L_x - \delta L_y = h(t) L[/latex]

It is on the order of 10^-21, and the arm lengths are 4km, which means (If I did the math right) the arms were shifting by about one ten-trillionth of the width of a human hair.

[edit2] - Fixed back-of the envelope estimate above

We both went for the same image. The editors of the site might want to merge this with an already opened thread on the Astronomy section of this forum (I already put in much of what you've just added - though it can't hurt to see it twice and this stuff is very interesting!)

Carawaystick

So for a slightly handwavey explanation to get it clearer in my head.
Are there 2 sources of gravitational waves here? The pre merger bit where 2 massive bodies are rotating about their common centre of gravity. These are changing the local curvature of space time so fast ( say inside a sphere of 2x the distance between their centres) that this is generating some gravitational wave energy

And the second process, the destruction of the 3sol of mass
This is like a step change in the gravitational field. you've gone from a 65sol mass gravity field to a 62sol mass gravity