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The following Physical Review D article gives reasonable bounds for gravitational wave detection for Supernova core collapse. These bounds cannot be overwhelmingly different from the bounds on GW detection from compact binary star ("black hole") collapse. However, to meet the LIGO claim of 1.3 billion ly to source, the bounds on detecting a "black hole" merger would have to be ONE or TWO ORDERS OF MAGNITUDE different from those of supernova core collapse. This seems unlikely.

The original article is at Phys. Rev. D 93 042002. If you do not have APS privileges, the article can be read in rough format (please excuse) at: https://integrativemind.wordpress.com/2016/02/24/observing-gravitational-waves-from-core-collapse-supernovae-in-the-advanced-detector-era/ (This is not the most related article, simply one I ran across today.)

Six other reasons I doubt the LIGO results:

1) Against all precedent, the American Physical Society announced the finding with absolute certainty. Major discoveries are always announced tentatively pending input from independent researchers. The Higgs boson discovery, for example, generated dozens of papers in Physical Review D questioning the results. This suggests APS and the LIGO group are exaggerating the claim.

2) The detection occurred right after a system upgrade. Lawrence Krauss at Arizona State University has said that the signal could have been a standard test pattern, accidentally or deliberately injected into the data stream. (https://www.newscientist.com/article/dn28754-new-rumours-that-gravitational-waves-have-finally-been-detected/) Had a test signal caused the detection, no one would admit it, even if they knew. Angry support personnel are not uncommon in astronomical research environments.

3) The signal looks too much like a textbook pattern. Usually an initial discovery has elements of surprise. For example, the predicted CMB temperature was an order of magnitude off from the observed 2.7K.

4) That the "source" was 1.3 billion ly distant is improbable for a first detection, given the weakness of gravitational signals. One would expect the first detection to be nearer the local cluster, out to perhaps 100 million light years (see above PRD article).

5) Physicists (such as James Hartle in personal conversation) admit black holes can never form by gravitational collapse, due to infinite time dilation at the event horizon. Two black holes merging might also be impossible. At best, the LIGO GW might come from a merger of compact binary stars. That they announced it was black holes suggests exaggeration.

6) Astronomical projects need money, and astronomers are known to distort results to insure future funding. Formerly employed at Kitt Peak, I have seen this first hand.

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closed as off-topic by John Rennie, Kyle Kanos, CR Drost, user36790, dmckee Feb 19 '16 at 18:49

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locked by David Z Feb 25 '16 at 5:31

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    $\begingroup$ I'm voting to close this question as off-topic because it's wild speculation untainted by either knowledge of physics or familiarity with the LIGO literature. $\endgroup$ – John Rennie Feb 19 '16 at 18:14
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    $\begingroup$ Possible duplicate of Is there absolute proof for gravitational waves? $\endgroup$ – CR Drost Feb 19 '16 at 18:17
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There is a very small chance the signal is fake. $5.1\sigma$ means less than 1 in about 1 750 000. The LIGO collaboration, themselves, say that if they collected data for 203 000 years, they would expect one false alarm of this significance. Maybe we're really unlucky... but lets address some of your concerns anyway:

2) The detection occurred right after a system upgrade. Lawrence Krauss at Arizona State University has said that the signal could have been a false one deliberately injected into the data stream for testing, although this was denied by the LIGO team.

The system upgrade made the detector much more sensitive than before, if this event had occurred before the upgrade LIGO would have missed it. For all we know this type of event occurred many times during the initial LIGO data collection, but the detector wasn't sensitive enough to observe any.

As for a blind hardware injection, LIGO uses blind injections to test the data analysis procedures. During a hardware injection, the test masses in the system are physically driven to simulate a gravitational wave. This event was not a scheduled blind injection. The LIGO team also checked if there was a system malfunction and a hardware injection was accidentally made at this time. There was not. Someone maliciously triggering an injection would have been noticed

3) The signal looks too much like a textbook pattern. Usually an initial discovery has elements of surprise

The fact that it looks textbook is strong evidence that General Relativity accurately describes the universe. We already knew that. The Higgs Boson and the Cosmic Microwave Background also looked pretty "textbook" at first. New physics may be revealed through gravitational waves, but it hasn't been yet.

4) That the "source" was 1.3 billion ly distant seems improbable for a first detection, given the weakness of gravitational signals. One would expect the first detection to be in our local glactic neighborhood.

No. Lets say one binary black hole system merges per galaxy per million years. Advanced LIGO can observe many millions of galaxies. What are the odds the first event should come from our own galaxy?

5) Many physicists admit that black holes can never form by gravitational collapse, due to infinite time dilation at the event horizon. Two black holes merging might also be impossible.

Who are these "many" physicists? Two black holes merging is absolutely possible in General Relativity. Check out any of the vast literature on binary black hole systems.

The "infinite time dilation" argument is one of the common misconceptions about GR that comes from people forgetting that GR is a non-linear theory, and the Schwarzschild solution only approximately works when a massive, non-point particle gets close to a single black hole.

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    $\begingroup$ The infinite time dilation argument just means there are compact stars that look and act very similar to black holes, so you can accurately model them by black holes. They can merge into a single compact star that is well approximated by a single black hole. The gravitational waves generated by the merger are very similar to the waves generated by two black holes merging. It isn't a reason to doubt anything. $\endgroup$ – Timaeus Feb 19 '16 at 19:53

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