Gravitational waves claimed to be detected by aLigo

[Urwumpe]

After analysis, the aLigo team is claiming that they really measured gravitational waves with their detector on the 14th September 2015.

https://www.sciencenews.org/article/gravity-waves-black-holes-verify-einstein’s-prediction

The paper about the discovery is cited as such, and has over 1000 authors (which really suggests some importance, if you need to put so many friends and pets there):

B.P. Abbott et al. Observation of gravitational waves from a binary black hole merger. Physical Review Letters. Vol. 116, p. 061102. Published online February 11, 2016. doi: 10.1103/PhysRevLett.116.061102

 

[boogabooga]

[Edit: Nevermind, I was thinking about something else]

 

[Notebook]

Its on the bbc, must be right...
http://www.bbc.co.uk/news/science-environment-35524440

N.

 

[Urwumpe]

Also around in German language, on Spiegel Online....

http://www.spiegel.de/wissenschaft/...sen-albert-einstein-bestaetigt-a-1076818.html

...and heise online:

http://www.heise.de/newsticker/meld...r-weisen-Gravitationswellen-nach-3099654.html

And Tagesschau also believes that this was important enough for urgent news.

 

[Thunder Chicken]

Link to paper here:

http://journals.aps.org/prl/abstract/10.1103/PhysRevLett.116.061102

You'll have to be patient - this is being downloaded by every physicist and their grad students (and we science geeks) right now.

 

[Quick_Nick]

I think the press conference is about to start ?
EDIT: I'm not sure what happened to the webcast, but I guess the conference happened or is happening.

---------- Post added at 10:50 AM ---------- Previous post was at 10:27 AM ----------

Link to paper here:

http://journals.aps.org/prl/abstract/10.1103/PhysRevLett.116.061102

You'll have to be patient - this is being downloaded by every physicist and their grad students (and we science geeks) right now.

Heheh

Until our servers are back online (we're adding more capacity now) here is figure one from the paper #LIGO

We're coming back online...in the meantime here are figures 2-4: #LIGO

 

[MaverickSawyer]

SO... They detected two black holes merging? :blink: Wow.

 

[Quick_Nick]

SO... They detected two black holes merging? :blink: Wow.

I hope someone will verify this but supposedly the merger very briefly produced more power than the rest of the observable universe combined ?!

 

[Artlav]

Hm, what makes me wonder is how the heck do they keep the noise out?
This thing measures shifts on the order of a width of a subatomic particle - one would expect that a bird crapping somewhere on the continent would produce enough of a seismic wave to be detected by this instrument.

supposedly the merger very briefly produced more power than the rest of the observable universe combined ?!

3 solar masses worth of energy got emitted as gravity waves alone, apparently.

 

[Quick_Nick]

---------- Post added at 01:47 PM ---------- Previous post was at 01:45 PM ----------

3 solar masses worth of energy got emitted as gravity waves alone, apparently.

500000000000000000000000000000000000000000000000 Joules!
EDIT: Or twenty quadrillion Earth-masses worth of TNT.

 

[kamaz]

Received 21 January 2016

And here we see how the peer-review system is broken as in most cases publication takes 6 months, not 20 days.

---------- Post added at 09:55 PM ---------- Previous post was at 09:47 PM ----------

Cute. Meow.

This would actually be audible

 

[N_Molson]

So how fast travel gravitational waves ? Speed of Light ? :hmm:

 

[Linguofreak]

This would actually be audible

Indeed it would. Not only are the frequencies in the right range, but it would actually cause mechanical vibrations in your body.

I just realized: This is the longest range at which an object has ever been detected by passive sonar. Shall I fire a torpedo, captain?

 

[kamaz]

So how fast travel gravitational waves ? Speed of Light ? :hmm:

Probably. Measurement produced 0.95 +/- 0.25 c.

https://www.newscientist.com/article/dn3232-first-speed-of-gravity-measurement-revealed/

Most physicists believe that it propagates at c, because if it moved faster (i.e. instantaneously) it would break causality, and there is no logical reason why it would move slower.

Note that this holds true only in vacuum.

 

[boogabooga]

And here we see how the peer-review system is broken as in most cases publication takes 6 months, not 20 days.

Good point.

Are "Review Letters" supposed to be fast-tracked early results perhaps?

I would expect that something more substantial will come out in Science/Nature in due time.

 

[Topper]

Link to the press conference:

 

[kamaz]

Are "Review Letters" supposed to be fast-tracked early results perhaps?

Contrary.

(PRA = Physical Review A etc., PRL = Physical Review Letters)

 

[boogabooga]

Much less than the median and the mean on this one, but still more than the minimum.

 

[Urwumpe]

Yes - minimum 7 days.

The question is: If you have 1000 authors, for a small paper, what does this paper really contain? How long would a peer review need of a paper, where most of the hard science is likely contained in referenced, more specialised papers produced by the individual teams behind the experiment?

You can actually have quite fast peer reviews that way - but the other papers behind might need even longer effort if there are more complex argumentations to follow.

Also, peer review does not require repeating the experiment. It only means confirming that the paper is sound and not already logically wrong, building on wrong assumptions or having technical errors in science. It can be done in days in simpler cases, the more specialized the knowledge to follow the argumentations, the longer the review takes.

And for some Indian journals, all that is needed for passing peer review there is to use the correct word template for the article and follow the style guide. We had a lot of fun during the basic "Scientific processes" lecture back then with those as example of how you should not do it.... or how you can reach high publication quotas with minimum scientific effort.

After all, yes, this paper was sure published as early as possible for preventing that somebody else is faster. And was sure written with that early publication in mind.

PS: And remember: You can still get a paper of the year award by the AIAA without ever passing a serious peer review.

 

[kamaz]

Naaaaaah.

The problem is something else. Since reviewers don't get paid, then a reviewer who gets the paper throws it at the bottom of the drawer and will only read it after three months and multiple e-mail reminders from the editor.

PS: And remember: You can still get a paper of the year award by the AIAA without ever passing a serious peer review.

AIAA lets through some hilariously bad papers.

That said, letting through bad papers is preferrable to suppression of results reviewers don't like, but cannot challenge.