It doesn't show any such dispersion. https://journals.aps.org/prl/pdf/10.1103/PhysRevLett.118.221101

It can be used to set bounds on any such effects. The bounds are consistent with there being no dispersion.

Yes stam 

YOu can believe what you are told -or your own eyes.

In all three mergers there has been dispertion - this one is best seen in the Livingstone trace (attached)

The fact that the  waveforms shown aren't monochromatic doesn't, by itself,  have anything to do with any dispersion of the gravitational waves themselves. So it doesn't make sense to use the former to discuss the latter. 

It suffices to read the relevant section of the paper, that does discuss dispersion.

Merging galaxies liberate gravitons . 

@STam

I reiterate, don't just rely on what you are told or read (this is known as critical thinking, which is very poorly taught).

If you look at the diagram there is a clear bifurcation in the signal, the question is what is the explanation for that bifurcation.

AW: If you look at the diagram there is a clear bifurcation in the signal,

Dispersion is not visible as other frequencies, it produces a small and monotonically varying delay in the signal depending on the chirp frequency so it would only show up as a time difference between the observed waveform and the wavelet filtered version in the lower two plots in your image which differs from the amount expected from precession of the black hole spins. The upper two plots show the wave amplitude as the magnitude irrespective of phase so automatically exclude dispersion.

AW: what is the explanation for that bifurcation

It looks like the alias signal you would expect from intermodulation of the astrophysical signal with other fixed frequency signals in the system such as the suspension resonance or one of the injected fixed-frequency calibration signals but that's just a guess, there are many possibilities.

Thanks all I have changed the question accordingly to bifurcation.

The thing is the unexplained  bifurcation appears in all three mergers

To me it doesn't look like a "bifurcation", it looks like a crossover of a lower level descending chirp added to the stronger ascending signal. That would be the characteristic of an alias, a mirror image in the FFT about a fixed frequency.

Looking at the GW151226 release, there seem to be two cross-overs, one at 60Hz which is the US power frequency and the other at 120Hz, its second harmonic. The implication is that the background noise is an intermodulation product with breakthrough of the local power supply.

https://losc.ligo.org/s/events/GW150914/P150914/fig1-freqtime-H.png

Hi George,

Actually what we are seeing is the inside of a black hole, the two crossover points are the crossing of two event horizons, the larger and the smaller.

It is possible to predict the frequencies of the GW and the precise ratios of the max and min frequencies of the bifurcations using this model.

With the third event showing this,the evidence is more solid. But it can be predicted that future events will follow this model

That doesn't work Andrew, the waves are produced by the orbital motion of the bodies, not the horizons. If there were two frequency components to the wave, the BH would have to have split into two parts, one orbiting slowly and the other more rapidly.

You don''t get it, the GWs change when they cross each horizon, one frequency is tachyonic the other is red shifted.

You don't get it Andrew, the waves are only formed several radii away from the binary system and move outwards, they never get anywhere near the horizons.

@ George

What twisted logic could ever imagine that the gravity does not emanate from a gravitational body.

Modern science is in serious trouble.

It's the same distinction as what are called "near field effects" in EM. Have you never used a contactless credit card, or picked up a pin with a magnet, or felt the 'static from a balloon rubbed on cloth? These phenomena are real but they are not Hertzian wave solutions.

Come on try to think, the charge of the electron still emanates form the electron.

Right, as does the Coulomb force (seen by an observer close to the electron) which gives us static electricity, but the wave format only becomes dominant at distance. Try to follow the analogy Andrew, there are differences in the format of the waves (quadrupole versus dipole) but this aspect is comparable.

I know what you mean, but what exactly is the dipole Vs quadrupole moment

More relevant is the effect of space-time - which we know has energy. 

We now call this quintessence , but was known as the aether

The wheel has been reinvented - but this time we Know it as "dark energy" or quintessence. - that is what transmits the effect you are talking of.

LIGO is film story

Good question Andrew, Hanford and Livingston signals on the whole follow theoretical predictions, given by the black line. The residuals are not exactly random noise. At some places Hanford signal is just out of phase with Livingston signal (0.54, 0.55, 0.59, 0.62), I am sure a lot of people are carefully looking at the residual pattern and deduce it's Physics implications.

Ref. http://pdg.lbl.gov/2016/listings/rpp2016-list-graviton.pdf

HI Biswajoy,

I have analysed the data without assuming GTR is necessarily correct. On this in depth analysis the bifurcation appears to occur at the event horizon.

Interestingly, if that is the case what we are seeing, using the gravitational wave telescope (LIGO), after the bifurcation  is what is happening inside the black hole itself.

@ Stam

I am now talking of bifurcation not dispersion. But still value you input

Be wise

What you are looking at is the next stage of discovery

Do not be bounded by the bounds of GTR

I doubt whether you actually know GTR (general theory of relativity). It is so complex that Einstein himself could not use it, which is obvious if you  read his original papers.

So if you can  show me how to calculate  the advance in the perihelion of Mercury (it is possible to do so readily), let me know.

@ A farti

Impressive 100 equations just to get an approximation.

Herein exact solutions in 4 lines of algebra (see appendices).

https://www.researchgate.net/publication/269689554_The_formulation_of_Dynamic_Newtonian_advanced_gravity_DNAg.

P.S. You wasted your time studying GTR.

Article The formulation of Dynamic Newtonian advanced gravity, DNAg

@ Andrew Worsley

my dear Andrew Worsley you are absolutely right ....The formulation of Dynamic Newtonian advanced gravity, DNAg good paper i have read recently....

@A Farti

You are confusing physics with an unnecessarily complex formula,.

Back onto topic,

Does anybody have a good explanation for the apparent bifurcation in the GW signals from LIGO?

You've been given one possibility already Andrew, an alias between the true signal and other fixed frequencies in the system. What analysis have you done to rule that out? Have you contacted the LIGO team to ask their opinion? They probably know already.

That only remains one possibility, and not a very plausible one at that.

AW: That only remains one possibility,

Sure, but let's start with the obvious first.

AW: and not a very plausible one at that

Why? I've spent many hours in the last couple of months proving that the aliases in the radio our team is designing are below the required limits and there is no question that this mechanism will occur in LIGO too.