New Gravitational Wave Discovery (Press Conference and Online Q&A Session)

AgentB
AgentB
Joined: 17 Mar 12
Posts: 915
Credit: 513211304
RAC: 0
Topic 210189

On Monday ... youtube link here

AgentB
AgentB
Joined: 17 Mar 12
Posts: 915
Credit: 513211304
RAC: 0

Well worth watching, explains

Well worth watching, explains many things about how discovered, the observations and discoveries.

I think this trumps the first GW - this is a rare gift.

Gary Roberts
Gary Roberts
Moderator
Joined: 9 Feb 05
Posts: 5842
Credit: 109391600090
RAC: 35875079

I found this youtube video

I found this youtube video which is quite short (just over 5 mins) but very informative about the significance of this neutron star merger as compared to the previous 4 BH-BH events.

I think it's really worth watching for anyone interested in why this new discovery is so important.  In an instant, the cause of gamma ray bursts has gone from theory to established fact and we now know where heavy elements like gold, platinum and uranium come from - just two things that immediately stood out from the presentation.

 

Cheers,
Gary.

Mike Hewson
Mike Hewson
Moderator
Joined: 1 Dec 05
Posts: 6534
Credit: 284710168
RAC: 110462

I've just briefly come back

I've just briefly come back on-grid today and seen this marvellous news !! :-)

It is epicepic ( epic to the power of epic ) because it has an electromagnetic confirmation also, has cracked open some old conundrums and whatever else will no doubt flow from this encounter. I agree that this is a rare gift ie. one of those weird exceptions that eventually define a new rule.

:-):-) 

Cheers, Mike.

I have made this letter longer than usual because I lack the time to make it shorter ...

... and my other CPU is a Ryzen 5950X :-) Blaise Pascal

Betreger
Betreger
Joined: 25 Feb 05
Posts: 987
Credit: 1421620904
RAC: 800660

What amazes me is that they

What amazes me is that they were able to so quickly mobilize the rest of the astronomy community and get useful observations. 

Mike Hewson
Mike Hewson
Moderator
Joined: 1 Dec 05
Posts: 6534
Credit: 284710168
RAC: 110462

The communication, admin

The triggers, communications, admin structures etc for exactly this scenario has been in place since the early days, both within and without the LIGO community. And event notifications going both ways to boot. I reckon this is one of the ( increasing list of ) reasons to celebrate. The system works. For sure the GW detectors are the most sensitive instruments ever constructed, but the payoff multiplier/exponentiator here is the correlations elsewhere. The theorists must be drooling .....

Cheers, Mike.

I have made this letter longer than usual because I lack the time to make it shorter ...

... and my other CPU is a Ryzen 5950X :-) Blaise Pascal

Gary Roberts
Gary Roberts
Moderator
Joined: 9 Feb 05
Posts: 5842
Credit: 109391600090
RAC: 35875079

Quote::-):-) Show-off!!!

Quote:
:-):-)

Show-off!!! :-):-):-)

Good to see you're still alive - wherever you're hiding! :-).

 

Cheers,
Gary.

Mike Hewson
Mike Hewson
Moderator
Joined: 1 Dec 05
Posts: 6534
Credit: 284710168
RAC: 110462

LOL !! :-)2As for the

LOL !! :-)2

As for the notifying process :

Quote:
On Aug. 17, LIGO’s real-time data analysis software caught a strong signal of gravitational waves from space in one of the two LIGO detectors. At nearly the same time, the Gamma-ray Burst Monitor on NASA’s Fermi space telescope had detected a burst of gamma rays. LIGO-Virgo analysis software put the two signals together and saw it was highly unlikely to be a chance coincidence, and another automated LIGO analysis indicated that there was a coincident gravitational wave signal in the other LIGO detector. Rapid gravitational-wave detection by the LIGO-Virgo team, coupled with Fermi’s gamma-ray detection, enabled the launch of follow-up by telescopes around the world.

Cheers, Mike.

( edit ) There is a legitimate analogy here with the Rosetta Stone.

I have made this letter longer than usual because I lack the time to make it shorter ...

... and my other CPU is a Ryzen 5950X :-) Blaise Pascal

tullio
tullio
Joined: 22 Jan 05
Posts: 2118
Credit: 61407735
RAC: 0

Virgo detected a very weak

Virgo detected a very weak signal. Since Virgo has 4 blind spots, the fact that the signal was weak meant it was coming from one of those spots and this allowed to find its source, in the galaxy NGC4993.

Tullio

Hans
Hans
Joined: 5 Oct 17
Posts: 7
Credit: 27600
RAC: 0

Isn't this what einstein@home

Isn't this what einstein@home was created for - to search for gravitational waves emitted by neutron stars? Was einstein@home in any way involved in the finding? As far as I can tell, the discovery of those waves was done "live", while einstein@home is searching through huge amounts of data. So do you discover GW by reading live instruments or by analysing collected data?

And what's the currents status and future of this project, since it's main goal was achieved? So many questions....

AgentB
AgentB
Joined: 17 Mar 12
Posts: 915
Credit: 513211304
RAC: 0

Hans_31 wrote:Isn't this what

Hans_31 wrote:
Isn't this what einstein@home was created for - to search for gravitational waves emitted by neutron stars?

Errm it's a little more complicated than that! Smile

  https://einsteinathome.org/about

Refers to singular spinning neutron stars, not a binary merger of two neutron stars.  The amount of gravitational wave energy released in such a merger is enormous and generates a "relatively" easy real time detected signal.

Quote:
Was einstein@home in any way involved in the finding?

Not that i know of, but there may be more to this discovery yet to be published.   It's not just "we found it!" :)

The #NSNS inspiral was emitting GW long before the merger, and it will be interesting to see what data exists in the earlier runs - this might be an E@H speciality.  I'm sure that is being given close attention!

E@H gets mentioned often in LIGO / VIRGO meetings and publications.

Quote:
As far as I can tell, the discovery of those waves was done "live", while einstein@home is searching through huge amounts of data. So do you discover GW by reading live instruments or by analysing collected data?

Both.  Live just means a short amount of processing time is needed to identify a strong signal in a data stream. 

Faint but regular signals, such as from a pulsar, the more data processing is needed to find signals.  It is this extreme regularity (in frequency) and long data runs which allows weak signals to be seen and noise filtered out, think of  several different clocks in a noisy football stadium ticking regularly, and you have a recording of all the noises from many microphones but only during football matches. If you average all the noises out for a long enough and it will take a long time to do this, the clocks will be found because nothing else is ticking regularly.

In some cases as little as 10 photons per day were enough to discover a pulsar spinning many times a second.  See here

See the long list of discoveries https://einsteinathome.org/science/publication

Quote:
And what's the currents status and future of this project, since it's main goal was achieved? So many questions....

E@H is not looking for binary NS merger events - but looking for continuous signals in EM/GW waves.  I'm sure we will hear more soon (from the project)!

 

Comment viewing options

Select your preferred way to display the comments and click "Save settings" to activate your changes.