Comments on: Direct Detection Of Gravitational Waves

By: zachdcox

zachdcox — Mon, 26 Mar 2018 12:00:02 +0000

The article mentions “Cosmological Redshift” to compute the distance to the event. For light waves from distant sources absorption and emission bands int he light are displaced and the amount of displacement gives the ‘red/blue’ shift of the object.

My question is:

What Plays the role of Absorption and Emission Bands For Gravity Waves?

By: Brian Koberlein

Brian Koberlein — Sun, 14 Feb 2016 22:15:50 +0000

Likely. I haven’t done the calculation myself, but it seems reasonable.

By: RabidAnt

RabidAnt — Sun, 14 Feb 2016 22:10:04 +0000

In a New Scientist article, Kip Thorne is quoted as follows:

“The total power output of gravitational waves during the brief collision was 50 times greater than all of the power put out by all the of the stars in the universe put together,” said Kip Thorne of Caltech, one of LIGO’s founders. “It’s unbelievable.”

It is unbelievable. Is he right?

By: MLAI

MLAI — Sun, 14 Feb 2016 04:59:01 +0000

So things *can* fall into black holes (in this case, another black hole) without taking an eternity (due to time dilation) for outside observers to observe the event!

Or is this a special case scenario because the infalling object is another black hole, so somehow the eternal time dilation isn’t applicable?

Or are gravitational waves not bound to the rules of time dilation, since gravity itself is simply a measure of the distortion of spacetime?

I’ll just sit over there and rest for a bit…

By: Göran

Göran — Sat, 13 Feb 2016 19:09:18 +0000

I’m a big fan of the podcast, is there any news of when the next episode will come out? Your articles are very interesting and insightful and your podcast is among the best of them! Sorry if this question is in the wrong place…

By: Steve

Steve — Sat, 13 Feb 2016 16:50:55 +0000

Is a 5% loss of mass something that depends on the characteristics of the black holes merging, rotation and relative speed to each other, or is it just based on the combined mass?

By: Ggreybeard

Ggreybeard — Sat, 13 Feb 2016 01:57:58 +0000

Brian, what exquisite science!
You stated that we know “the cosmological redshift of the event (which is how we know its distance)”.
I fully understand that electro-magnetic waves contain the redshifted emission/absorbtion signatures of the various elements.
However, could you expand a bit on how evidence of redshift is coded in gravitational waves?
🙂

By: Anton

Anton — Fri, 12 Feb 2016 22:41:56 +0000

This is too exciting for words. The best part is that FINALLY there is observational evidence for Black Holes.

By: Jpatrick

Jpatrick — Fri, 12 Feb 2016 20:08:41 +0000

One aspect of the significance of detecting gravity waves is not so much the confirmation of general relativity, but that now we have a benchmark that will allow us to get better at how to do this. In a few generations, a gravitational telescope will make LIGO seem quaint and crude.

By: Jean Tate

Jean Tate — Fri, 12 Feb 2016 19:36:50 +0000

I agree that the gravitational effects of the BHs themselves would likely shred anything close (tidal forces), but consider a minimal mass white dwarf, say, at a distance where it would not get spaghettified: how would such an energetic GW from the BH merger affect it? Also, what about dust, molecules and atoms; even close to the BHs they’d not be ripped to individual atoms or ions by the tidal forces (or would they?), but how would they be affected by the passing GWs?

By: Brian Koberlein

Brian Koberlein — Fri, 12 Feb 2016 18:37:44 +0000

1. Yes. 2. Good question. I’m sure people are working on that.

By: Brian Koberlein

Brian Koberlein — Fri, 12 Feb 2016 18:37:09 +0000

I haven’t worked through the calculations, but I imagine anything close to the black holes when they merged would have been torn apart by the gravitational forces.