On 31/05/2017, LIGO claimed that they detected the gravitational wave third time. But, many scientists in the reseaechgate.net doubt their detection and presented many questions. However, in the researchgate.net, there are the scientists of the whole world. It seems that it is the duty of LIGO to answer these questions. So, I suggest that LIGO should have an open answer for these questions to clarify their detection with the scientists of the world.
To clarify this detection, it need be clarified from the fundamental theories. Because the gravitational waves are produced from the emerge of two black holes. So, the first fundamental question is:
How to know the position and motion of a black hole? What is the first observation that confirmed that a black hole was detected?
I hope other physicists to present their questions. And, any scientists are welcomed to answer the questions.
The direction can be deduced because there are 2 LIGO stations.
As usual the experimentalists have been quite thorough. It is the theorists that have GTR wrong there should ber no dispertion of gravitational waves but there is a bifurcation in the chirp in all 3 experiments.
tHERE IS SOME EXPLAINING TO DO.
LIGO data is helpful to my project, checking consistency, but I am concerned about the secrecy of LIGO.
Dear Jerry, not only at LIGO some people knows their secret... It seems that you know, too.
Best regards,
Laszlo
Ligo detected not waves rather gravitons . Spring balance could detect the same .
pl read attachment
Dear Dr. Das,
Thank you for your information.
I agree with you that the gravitationa radiation produced by the binary star observed by Hulse and Tayler is questioned. The heat and electromagnetic radiation is much larger than the gravitational one. The orbit varied by the heat and electromagnetic radiation should be much larger than that observed by Hulse and Tayler.
now a days physics became commercial and showness ...they (LIGO) are telling stories ..we are not suppose to follow blindly.... because their is no proper evidence of having black hole story .... it's all nonsense and wasting of time....
http://www.keckobservatory.org/recent/entry/new_method_of_searching_for_fifth_force
@ Adrian Sfarti
my dear Adrian Sfarti we are not film directors to read film stories of LIGO website....got it?
if you have that much interest to read stories you read it....got it?
@ Adrian Sfarti
my dear Adrian Sfarti why always you try to prove " Adrian Sfarti is a empty vessel"........
proof: we are here to talk subject, convince subject, explore subject etc...but you always talk in useless manner as given answer above....
if you don't know anything just keep pause don't talk unnecessary things plz...
Are LIGO's Detections Just Nois? Edit
A team of five researchers — James Creswell, Sebastian von Hausegger, Andrew D. Jackson, Hao Liu, and Pavel Naselsky — from the Niels Bohr Institute in Copenhagen, presented their own analysis of the openly available LIGO data. And, unlike the LIGO collaboration itself, they come to a disturbing conclusion: that these gravitational waves might not be signals at all, but rather patterns in the noise that have hoodwinked even the best scientists working on this puzzle
arXiv:1706.04191v1 [astro-ph.IM] 13 Jun 2017].
For decades, theory and observation suggested that stellar black holes couldn’t exceed roughly 10 solar masses.The black holes LIGO has seen, though, are somewhere in the middle—in the range of tens of solar masses. We’ve always assumed that black holes of this mass range should probably exist, but they’re hard to find evidence for in observations. So why has LIGO seen these, and not the smaller stellar-mass black holes everyone expected? But not everything is as physicists expected. The ripples we’ve seen were produced by black holes more massive than we thought we would find.
Maybe the problem of internet, sometime, I cannot read this question. So, I did not reply some problem at once.
Now, I have a simple introduction about the two black hole merging.
In the papers by LIGO, it was declared that he gravitational waves are produced by the two black holes merging. Almost every reader thinks that the two black holes merging was observed by LIGO.
However, this is not true. The two black holes merging has never been observed.
In fact, now, the black hole has not been certainly observed. Theoretically, the black hole cannot be directly observed for that nothing can escape from a black hole. Therefore, a black hole only can be indirectly known by observing the variation of the orbit of the celestial bodies near this black hole, the light bended and electromagnetic field varied by this black hole. Now, we have not certainly observed a black hole through these ways. Thus, it is certain, the black holes merging has not been observed by LIGO.
In the work of LIGO, the black holes merging was only calculated with the numerical relativity. And, LIGO had explanatory note that they have not known the direction of the merged black hole. Thus, they cannot know the variations of orbit, light line and electromagnetic field near the two black holes. Therefore, the black hole merging has nothing to do with observation.
Then, why “Almost every reader thinks that the two black holes merging was observed by LIGO”? I think, it was misled by the declaration of LIGO.
LIGO had a very detailed description about the black hole merging. And, in the report for un-specialists, they have never clearly told them that the black hole merging only is a calculated conclusion. So, till now, not only the general readers, but also almost all of the physicists wrongly think that the two black holes merging was observed by LIGO.
It is clear, if the black holes merging is not an observation, the gravitational waves from this merging becomes little credible. So, some think that there is fraud.
Yes,
But it detects a bifurcation in the gravitational-waves, what is the due to?
YZ: They only knew the distance of the two black holes.
The smallest distance just before they merged sets a maximum diameter for the objects. They also know the masses of the two objects. The combination of those two rules is what implies they are black holes, because they far exceed the maximum mass for neutron stars and are too small to be stars.
Look at the relationship of diameter to mass for a main sequence star and you'll see what I mean. Even the smallest active stars, brown dwarfs, would be much larger than the observations permit. Only a neutron star approaches the density required and current understanding of their equation of state rules out anything above about 3 Solar masses. The largest known is about 2 Solar masses and that empirically appears to be very close to the real maximum mass limit.
http://www.daviddarling.info/encyclopedia/M/mass-radius_relation.html
Dear Henk Smid,
The merging of two black holes is a such a process: BH A+BH B =BH C. Therefore, it should be observed that, on one point of the Earth, at a certain disctance and direction, two BHs (or some of indirect signs of the two BHs) disappear and a BH(or some of indirect signs of the BH) appears. But, LIGO have not known the direction of the two BHs. How can they observe BH A+BH B =BH C?
YZ: How can they observe BH A+BH B =BH C?
The properties of the bodies are all calculated from the shape of the received waveform.
YZ: Only one signal was detected.
That's a bit ambiguous, signals have been detected on four separate occasions and in each case the signal was detected independently at both sites, but the gravitational wave itself is the same in each case which I think is what you meant.
The distance between the sites is 3000km which is tiny in comparison to the distance to the source so of course we expect the same pattern of strain at each site, but there will be slight differences in the electrical waveforms due to the differing orientation of the arms.
Yes and that gives us confidence that both sites were seeing the same astrophysical signal. If they differed, it would have been unexpected and puzzling.
YZ: I can image that this signal is from two black holes from 1/2, 1/3 of the distance
The published results of course include the uncertainty on the luminosity distance but that would still leave the source as two black holes.
YZ: or from merging of two planet
The frequency of the chirp is easily measured from the waveform. The circumference of the orbit of the objects has to be less than the period times the speed of light and the radius must be less than that divided by 2 pi, that's give the maximum radius. Planets would be larger than that separation so could never get that close.
The rate of change of the frequency can also be measured. Comparing that and the frequency tells you the chirp mass which is many times that of the Sun.
YZ: or from some kinds of shock in the Earth,
Those would be picked up by the seismic sensors.
YZ: and so on.
So you can't think of any credible alternative. That's OK, neither can anyone else.
Point 1: You suggested the signal could be "some kind of shocks in the Earth" but that would have been picked by the sensors so your suggestion is ruled out.
Point 2: See equation (1) on the linked page.
https://en.m.wikipedia.org/wiki/Chirp_mass
No, this is what I wrote, it is the last post on page 4:
2. "Hulse and Taylor confirmed the formula many years ago on a system far from merger."
I have emphasised the bit you seem to be unable to read.
OK, I'll say it again and try to be very clear.
- LIGO has observed a gravitational wave signal from the merger of two compact bodies.
- The maximum frequency measured gives an upper limit for the diameter of the bodies.
- The equation I linked give a measurement of the "chirp mass" which is a combination of the two individual masses.
- The only known objects that can have masses that are as high as was measured, in a diameter smaller than the upper limit that was measured, are black holes.
The LIGO team has therefore deduced that they have observed the merger of two black holes (on four occasions).
GD: I think you clearly sentenced your opinions. So, my words is not reply for you. The next words is my opinion.
1. The black hole cannot be directly observed. It only can be indirectly observed with the object near the black hole, such as the motion of celestial bodies, magnetic field. Now, the black hole has not been confirmed with indirect evidence.
2. LIGO have never observed the merging of two black holes. They have not known the direction of this merging.
3. LIGO detected some kinds of signal which they claimed that this signal is the gravitational waves.
4. But, this signal may be: 1) merging of two black holes. 2) earthquake which is very weak that cannot be detected with general gravimetor/seismometer. 3) only noise. 4) some kinds of conclusion accordant with a special parameter for the instrument.
Henk, you might find the response from the LIGO team member on this to be more informative and down-to-Earth, see the link.
http://www.preposterousuniverse.com/blog/2017/06/18/a-response-to-on-the-time-lags-of-the-ligo-signals-guest-post/
https://www.nobelprize.org/nobel_prizes/physics/laureates/1993/press.html
Of particular interest has been the possibility of verifying with great precision the theory's prediction that the system should lose energy by emitting gravitational waves in about the same way that a system of moving electrical charges emits electromagnetic waves.
Ligo saw missing mass, or computed missing mass?
First they measured the bouncing on Earth, then they started to look for its source.
Was the detection of gravitational waves manipulated? I cannot know.
But, it is clear, the press conference was manipulated: The observation of the collision of the neutrons stars is reported at the same press conference. Why the two observations can be reported at the same time and treated as same one "big news"? Why the researchers who observed the collision did not report their results independently?
Whether or not the detection is true, many people do not like a manipulated report.
However, there are scientific problem in this detection.
First, as presented previously, the waveform of a gravitational wave from a distance almost 10 billion lightyears must be varied for that its energy can be varied by the instruments of LIGO. But, in this detection, it almost was not varied.
Second, it is well-known that, a light ray can be bended by gravity. So, a light ray from a distance almost 10 billion lightyear is not running in a straight line. But, what is the line that a gravitational wave is running? Now, we have not had a certain knowledge. There is a Bi-metrics theory for this problem. In it, the gravitational wave and light ray are running in different lines. It is concluded that, in the distance of 10 billion lightyears, a gravitational wave should be later almost 6 days than a light ray to arrive at the Earth.
A general reader can have not the knowledge about the line that a gravitational wave running is different from that a light line running. But, LIGO have to tell the readers that what is the line that the gravitational wave is running and when it arrived at the Earth comparing with a light ray.
I read a very interesting article in Chinese in
http://blog.sciencenet.cn/blog-1319915-1082511.html
Many problems were discussed in detailed here.
YZ: Why the researchers who observed the collision did not report their results independently?
The optical observatories were told about the event 40 minutes after it happened by LIGO. They also said where to look, how far away it happened and the chirp mass.
After that, it still took them over 12 hours to find the nova. Without the information from LIGO, it would probably never have been found.
Much of the importance of the observations comes from combining the information from LIGO and the other observatories.
The neutron star merger was only 130 million light years away, much closer than the black hole mergers. We can see the galaxy clearly in the optical telescopes so we can see it is not lensed.
Solution of Einstein's equations for two merging black holes or neutron stars does not exist. What are we discussing?
This is translated from Chinese:
http://blog.sciencenet.cn/blog-224732-1082998.html
In August or July, a team obtained an analyzing conclusion. It showed that, after the signal of gravitational waves is abstracted, there is a time sequence relationship in the "noise" in the data. Principally, the time sequence relationship is a problem. It means that LIGO's filter algorithm is questioned.
Hello Yin Zhu,
I see the problem existed within the theoretical point of GW, not only to the experimental detection. In my view, such measurement (if true) measured the presence of spactime actually as spacetime is omni-present whether there is such source or not. You could see https://www.researchgate.net/post/Does_Gravitational_wave_correspondence_to_electromagnetic_nature_as_how_light_do and https://www.researchgate.net/post/Does_the_gravitational_wave_detection_is_real .
Dear Dr. Mohsen Lutephy,
Till now, LIGO claimed that they have detected the gravitational waves for more than 10 times. But, no other message, such as the gamma rays, has been observed. So, now, their results was doubted by many people. Espicially, the mainstream physicists begin to doubt them.
best
Dear Dr.Mohsen Lutephy,
Please read:
The LIGO Scientific Collaboration, Search for gravitational-wave signals associated with gamma-ray bursts during the second observing run of Advanced LIGO and Advanced Virgo, arXiv: 1907.01443
They had several papers for this problems. In my understanding, these papers mean that, even LIGO themself also think that they need other evidence for their conclusion.
best
Forgive me if I repeat that the discovery of the new fundamental science of Cryodynamics, sister of Thermodynamics, has confirmed Zwicky 1929.
Hence there is no Big Bang, and c is a global constant of nature again. A thousand consequences follow suit.
Guys, there is information about the whole stream at the detectors, along with noise:
LIGO observing run 1 from 2015-09-12 to 2016-01-13
https://www.gw-openscience.org/detector_status/O1/
LIGO observing run 2 from 2016-11-30 to 2017-08-25
https://www.gw-openscience.org/detector_status/O2/
LIGO+Virgo observing run 3 from 2019-04-01 til now.
I see seriously two anomalies in the distribution of the signal at the second run and Captain Obviousness asks what you want from 2016 or 2018?
Elementary, even if we do not go into questions about the likelihood of the onset of two events with one or another interval, and we will not multiply this by a duty factor of interferometers, etc.
By the way, the current status of the detectors is here https://ldas-jobs.ligo.caltech.edu/~gwistat/gwistat/gwistat.html
The discovery of the new fundamental discipline of Cryodynamics, sister of Thermodynamics, implies that there is no cosmic expansion and there are no gravitational waves. Forgive me that I am repeating myself.
But without a prior refutation of Cryodynamics, all of the well-presented arguments in favor of gravitational waves are, unfortunately, non-cogent.
Of course, a new science is a rare accident in science. I ask everyone's forgiveness for my seriously believing in (and having proved the validity of) Cryodynamics.
I am new to this question but there are several such discussions on Research Gate. If anyone interested, I uploaded a paper on ResearchGate showing that most GWs were within hours of New/Full Moon, perihelion, or another source of high tides. Also you may read https://backreaction.blogspot.com/2019/11/have-we-really-measured-gravitational.html
....Opinion only about measurements...:
Is the detection of a gravitational wave by LIGO true?,
As the measurements taken by the interferometry - Yes.
Sources of these gravitational waves (or other waves detected by LIGO) are the other questions for physicists/cosmologists.
Gravitational waves are hoax/fake . .. .. . …Other than many authentic reports sent to me (and on the internet) describing/disclosing how false they are , we ought to bear in mind that gravitation, by its very definition, and according to what we have actually learnt from Prof Einstein, simply CANNOT have waves.
You are welcome , Very Dear Yin Zhu . . . . I have gotten a Master's degree in physics and a PhD in biophysics .. . So I did not actually do anything wondrous to try to answer that question . . . I suppose the wonderful thing was truly committed by you who have a degree in agronomy , but at the same time you do your best to keep up with other branches of science . . . More Power To Your Elbow !! I wish other members of the world scientific community were as curious and as sharp as you , Sir !
Ligo detected only an artifact, many orders smaller than the detection limit.
Dear Dr. Reza Sanaye
Thank you very much for your kind words.
I think, for a scientific problem, prefer to the Master degree or PhD, the scientific standard is important.
And, I think, any scientific problem need be discussed publicly no mater who presented.
My main effort is devoted to physics. I had a work https://www.researchgate.net/publication/335352630_Pondering_and_exploring_of_modern_physics
If you are interesting in it, you are welcome to have a glance at it.
Best regards.
I shall read your article, Sir . . .. We two may write together . . .. .
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