With the caveat that I have nothing to do with ligo and so don't know much...<p>I <i>think</i> that during this ligo run (it just turned back on in April-ish) they expect to find roughly 1 event per week. So this will be fairly common! [1] is a nice summary of what they have found so far.<p>For people here interested in the engineering side of LIGO, it is absolutely mind blowing. The effect of the gravitational waves is tiny (fractions of the size of a proton change in length) and so there are so many things that need to be incredibly tightly controlled for. I went to a talk on this a year or so ago, but can't find the slides... Here's a summary [2] and the wikipedia page also has some info.<p>1 - <a href="https://www.sciencenews.org/article/ligo-virgo-made-5-likely-gravitational-wave-detections-month" rel="nofollow">https://www.sciencenews.org/article/ligo-virgo-made-5-likely...</a>
2 - <a href="https://www.engineering.com/Education/EducationArticles/ArticleID/14333/Engineering-the-LIGO-Gravitational-Wave-Detectors.aspx" rel="nofollow">https://www.engineering.com/Education/EducationArticles/Arti...</a>
Ok, their twitter humor is on point: <a href="https://twitter.com/LIGO/status/1145427537629208577" rel="nofollow">https://twitter.com/LIGO/status/1145427537629208577</a><p>edit: actually all their replies are hilarious.
This will sound cynical, but at this point, it's no longer news unless it's a binary neutron star merger. If there's an electromagnetic counterpart, then it's <i>big</i> news.<p>If you have a gravitational wave detection with an EM counterpart, you can get a redshift and luminosity distance, which means that you can measure the Hubble constant (in a way that is completely independent from Type Ia Supernovae). Binary black hole mergers are not expected to give off any EM radiation.<p>There should be a few binary neutron star mergers this run, and with some luck, there may be one with an EM counterpart.
Yes, the experimental details are stunning, particularly with an experimental physics background.<p>As someone who had a narrow escape from a PhD working on resonant bar-type detection attempts, I've never understood how those were ever thought to be sensitive enough -- whether decent calculations just weren't available or what. Unfortunately, you're typically not in a good position to evaluate such things before starting the work.
Can anyone explain how I should be reading that graph?<p>I'm surprised that the gravity anomaly is coming from a large region of space. And it's a curve. Is that expected? Why is it happening?<p>A black hole merge is coming from a single point in space, so I would have expected there to be a single point. But I'm definitely missing something.
I'm fascinated about the degree of automation. It seems that all the necessary computations are made and presented on that website. I would love to learn more about this and their tech stack.
Was there not some severe doubt on the whole signal inference? I recall an article that critized them for some changes in the protocol and also questioned the statistical significance of their findings. How is the current state of that discussion?
19 candidate events past 92 days since the improved system was turned on- about every five days.<p>I am not sure what elevates a candidate to a confirmed event.<p>Candidate events are posted quickly in hopes of observing associated photons.