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Re:Gravitational-wave detector LIGO is back by Gare on Friday May 26, 2023 @03:45PM (#36088702)
Re:Gravitational-wave detector LIGO is back by bsder on Friday May 26, 2023 @04:36PM (#36089219)
That event is amazing.

I had no idea how much cross correlation they produced (see the "Scientific Importance" sections). I love the fact that measurements got like 10 orders of magnitude or more better--that's just absolutely absurd.

Re:Gravitational-wave detector LIGO is back by throwawaymaths on Friday May 26, 2023 @11:08PM (#36091727)
You can't take two detectors and just say "they correlate" without presenting the blinded correlation data. If you apply the crazy filters that they do, how many of those signals happen in both detectors by chance?

In fact, you can't do a proper statistical analysis without three identical detectors, or at least two pairs of detectors, which we will have once ligo1,2 and Virgo are all online at the same time, and watch how the filtered signals drop in count based on how many detectors you look at.

> It is the first GW observation that has been confirmed by non-gravitational means.

This is a pretty weak claim. Worryingly, iirc it is the only multi-messenger observation we've made to date, so, again. How many supernovae do we see at any time in any given segment of the sky, and what is the likelihood that it would have happened to be in whatever ~1/20 spatial angle the Gw detectors happen to have resolutions over, and out of the other n candidate neutron-neutron mergers we've "detected" what are the odds that we wouldn't have seen a supernova in the EM by chance in all of the others?

If almost every single event came with a mm detection, I'd be convinced, but honestly, IMO it's looking kinda grim right now. We will find out if after we jack up the sensitivity we continue to fail to make multi messenger observations at the same rate as we have so far

Re:Gravitational-wave detector LIGO is back by pharrington on Friday May 26, 2023 @11:31PM (#36091848)
> How many supernovae do we see at any time in any given segment of the sky, and what is the likelihood that it would have happened to be in whatever ~1/20 spatial angle the Gw detectors happen to have resolutions over, and out of the other n candidate neutron-neutron mergers we've "detected" what are the odds that we wouldn't have seen a supernova in the EM by chance in all of the others?

The data's all publicly available. You go ahead, do the general relativity, and tell us.

Re:Gravitational-wave detector LIGO is back by throwawaymaths on Saturday May 27, 2023 @12:49AM (#36092149)
GR is unnecessary. This is a question of statistics.

>The data's all publicly available

No, it's not. Even if it were, the software and algorithms to do the statistical analysis on the raw data are not open source.

Re:Gravitational-wave detector LIGO is back by seanhunter on Saturday May 27, 2023 @03:26AM (#36092759)
I think the data is all publicly available, complete with software, sample python notebooks, tutorials etc.

https://gwosc.org/ and https://www.ligo.caltech.edu/page/ligo-data