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The New Wave of Gravitational Waves

I think it’s very sneaky of the LIGO Scientific Collaboration and the Virgo Collaboration to have released two new gravitational wave papers while I was out of circulation fora  couple of days, so I’m a bit late on this, but here are links to the new results on the arXiv.

You can click on all the excerpts below to make them bigger.

First there is GWTC-1: A Gravitational-Wave Transient Catalog of Compact Binary Mergers Observed by LIGO and Virgo during the First and Second Observing Runs with this abstract:

Here is a summary of the properties of the binary systems involved in the events listed in the above paper:

There are several (four) events in this catalogue that have not previously been announced (or, for that matter, subjected to peer review) despite having been seen in the data some time ago (as far back as 2015). I’m also intrigued by the footnote on the first page which contains the following:

…all candidate events with an estimated false alarm rate (FAR) less than 1 per 30 days
and probability > 0.5 of being of astrophysical origin (see Eq. (10) for the definition) are henceforth denoted with the GW prefix.

The use of false discovery rates is discussed at length here as a corrective to relying on p-values for detections. The criteria adopted here don’t seem all that strong to me.

The second paper is Binary Black Hole Population Properties Inferred from the First and Second Observing Runs of Advanced LIGO and Advanced Virgo which has this abstract:

I’ve been teaching and/or preparing lectures all day today, so I haven’t yet had time to read these papers in detail. I will try to read them over the next few days. In the meantime I would welcome comments through the box about these new results. I wonder if there’ll be any opinions from the direction of Copenhagen?

UPDATE: Here’s a montage of all 10 binary black hole mergers `detected’ so far…

I think it’s safe to say that if GW151266 had been the first to be announced, the news would have been greeted with considerable skepticism!

This entry was posted on December 4, 2018 at 5:24 pm and is filed under The Universe and Stuff with tags , , , , . You can follow any responses to this entry through the RSS 2.0 feed. You can leave a response, or trackback from your own site.

5 Responses to “The New Wave of Gravitational Waves”

  1. Alex Says:
    December 5, 2018 at 1:32 pm

    All 4 of the new ones have masses around 30 Msun? This is getting very bizarre…

    Reply
  3. Thaddeus Gutierrez Says:
    December 23, 2018 at 7:12 am

    The O2 catalogue [arxiv:1811.12907] advances lower SNR GW candidate triggers to ‘bonafide discoveries” than those rejected in Nitz et al. 2018 for O1 [arxiv:1811.01921]. The Nielsen et al. 2018 [arXiv:1811.04071] and Nitz et al 2018 LIGO authors abruptly left the collaboration as a response to this crisis, but are also referred to by LIGO and in new articles in Ars Technica and Quanta as “independent,” although they wrote these papers while members of the LIGO collaboration. This is not the first sign of trouble in paradise.

    LIGO decided to release four new triggers that have “network SNR” below their own seemingly-rigorous false discovery threshold. LIGO dredged their old data, and only one of these new four triggers even registers at more than one LIGO station with proper lag and SNR above colored non-Gaussian noise (noise exceeds signals in all LIGO events by at least three orders of magnitude). This particular more reliable signal, GW170729, was too dissimilar from numerical relativity templates that it could not be fit by the very modeling that provides confirmation of parametric consistency with GR.

    Now, six so-called GW signals out of a total of 11 arrived during the most lightning-active month for North America preceding the most active and energetic solar flare cycle in 12 years – all in under 30 days (conforming to a major Solar rotation cycle and its correlated driving of lightning cycle), and all during vigorous pulse-coupled CG from mesoscale quasi-stationary T-storms in LIGO line-of-sight (continuing the trend for previous N=7 LIGO events that had been established).The events again were synchronized with magnetospheric sawtooth oscillations and steady magnetospheric convection, with major changes in sunspot number. All 11 GW events arrived during remarkable substorm days. Multiscale foreground signal correlations persist with O2 N=4, with times of day and day of arrival preserving cyclicity synchronized with substorm phase, having very much identical autocorrelations. Magnetospheric sawtooth events only occur an average of 11/yr, and each of the 11 LIGO events coincided with a sawtooth event with intervals steady convection of solar wind.
    LIGO-Virgo interferometers are sensitive to many kinds of seismic and electromagnetic noise. The Earth’s magnetic field can become richly-structured, with quasiperiodic boundary intersections dominating interplanetary magnetic field data. Some of these intermittent states, collectively known as ‘magnetospheric mode,’ contain scale-invariant superpositions of chirp-like bifurcations and error-like paired boundary-like effects with transverse vacuum-like delta potential gaps, expected by many-body KAM theory and readily fit to a sufficient-degree of confidence by numerical relativity two-body interactions. Strongly-coupled geomagnetic response to Solar wind produces GW-like chirp transients in phase information, similar to EM ‘whistlers,’ but encoded into MM interferometer phase modulation. These match the waveforms used by LIGO and are common candidate events, as they can affect both detectors like a gravitational wave. Suspiciously, magnetometers have never been reported to have been fully functional and collecting quality data, but their failures, disconnections, and channel saturation issues are found throughout recent LIGO papers.

    Reply
  4. rick Says:
    January 7, 2020 at 1:26 am

    Dear Prof. Coles: Have you had a chance to examine the papers mentioned in this blog post? If yes, please what are your thoughts?

    Reply
  5. rick Says:
    January 7, 2020 at 4:46 am

    Prof. Cole: Please what are your thoughts on the papers now that you have reviewed them? I apologize for re-posting, but I am a young scholar trying to learn.

    Reply

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