Hi,

1) No, in principle any interaction with gravitational field where you change the quadrupole moment of mass distribution can produce G.W.

2) There are. Collision of neutron stars for example.

3) Single black hole do not produce G.W. because it does not have quadrupole moment. See no-hair theorem and similar ideas.

4) Well, this question can be understood in a way that you are asking for details of merging of two black holes. These details are very complicate, but if you want to understand just a general features of this process you can study the so called Black hole thermodynamics. In this view, the reason for merging of two black holes is the natural tendency of entropy to increase.

5) I am not sure what speed are you referring to. The relative speed of two distant object cannot be uniquely defined within the theory of general relativity.

The essential in items 1 and 2 is that the bodies are waves are produced when the orbiting each other just prior to merging.

For item 3, there is a brief "ringdown" when the shape oscillates while smoothing out but the waves are of much lower amplitude.

Item 4 is because the waves produced carry away orbital energy so the separation in the binary system gradually reduces.

The answer to 5 is that the period of the gravitational waves is half the period of the orbit of the binary system. The 'chirp mass' can be found from the derivative of the frequency versus the frequency and that combined with Kepler's Laws gives you the speed of the bodies in the last few complete orbits. (A full GR mathematical analysis extends that to the speed during the final merger.)

Dear Mohamed,

Take the next only informative: It’s alternative explanation, because the LIGO explanation of gravity waves is made such a way to attract your attention from the real explanation:

In the subject I have three works:

(1) Tényekkel igazolható a gravítáció valós oka (Gravity can be demonstrated with fact)- an real phenomenalogically explanation of gravity.

https://www.researchgate.net/publication/277364319_Tenyekkel_igazolhato_a_gravitacio_valos_oka

(2) “A tudomány kényes kérdése”: Sensitive phenomenon of theoretical science:

https://www.researchgate.net/publication/313632704_AZ_ELMELETI_TUDOMANY_KENYES_JELENSEGE

There is mentioned that the Earth tides and Earth quakes producing gravity waves visible to everyone from us. For this in the first part is shown that the Newton’s and Einstein’s theory of gravity has no causal explanation for this is not accepted “discovery of GW150914.

(3) A 2017. Fizikai Nobel-díj „gravitációs hullámai” (The ’gravitational waves’ of 2017 Nobel Prize in Physics). https://www.researchgate.net/publication/321641934_A_2017_Fizikai_Nobel-dij_gravitacios_hullamai There is showed that the Nobel Committee gave the prize of physics onto not scientifically reason. In the article is well shown with own and others researchers that SR and GR theories of Einstein cannot be used in real physics. So the prediction of GW’s explanation is also no-real validity. Was given an example of physics: how they (LIGO) could produce artificial: The paper has English: abstract and conclusion

(4) Exist an article: Planet Erosion…

http://planeterosion.blogspot.hu/

a real condition in the inner asteroid belt that shows that every rocky planet could get such a condition, when onto its surface the gravity field is null:

My Regards:

Laszlo

Second time derivative of the quadrupole moment of a mass distribution should be non zero; otherwise amplitude of emitted gravitational wave will vanish. This result was originally given by Einstein. Such conditions are satisfied by black hole merger events. Also, one thinks of existence of gravitational waves of primordial origin produced during inflationary era.

Dear Mohd.,

The supposingly found GW waves are not different from the amplitude differences of gravity that is obtained from the Moon orbiting the Earth.

With the merging of fast spinning stars ("black holes"), the periods are much shorter and the gravity fields stronger.

It is the fast orbiting approach, not the collision, that produces the alleged GW.

An electromagnetic antenna can produce a dipole signal, because it is attached to the Earth. However, a single mass, even a pulsating mass, will produce a steady gravity field seen from a large distance.

So, no dipole gravity field can be produced by single masses. With two orbiting masses, one comes straightforwardly to quadrupole moment systems.

The merging of black holes will affect the smallest one, which will be (partly or totally) disrupted (by tidal forces), be ejected at (super-)luminal speeds and decay to gamma-rays, which are seen from the Earth as X-rays.

The speed before merging was not measured. It was a computer simulation with a lot of suppositions, which was made to fit the "detected" (more probably "injected") data.