# GRAVITATIONAL WAVE AND MATTER

Discussion in 'General Science & Technology' started by ajanta, Oct 28, 2016.

1. ### ajantaRegistered Senior Member

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Simply matter has gravity. But does gravity exist(simply) without matter ? Suppose there is a supper massive black hole at the point A and gravitational wave of this black hole is detected at point B(which is half light year far away from point A)
So now, If the black hole is converted into energy ( theoriticaly) then will it be possible to detect gravitational wave at point B ?

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3. ### quantum_waveContemplating the "as yet" unknownValued Senior Member

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One of my first threads here was titled, Mass "has" gravity", so seeing the term used brings back memories. My premise is that mass, like a black hole, emits and absorbs gravity, so it would still exist even after filling the surrounding space with gravitational waves. On that basis, the gravitational waves, after being emitted, would exist whether or not the black hole disappeared. Never-the-less, I don't see the black hole disappearing as a result of emitting gravitational waves.

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5. ### ajantaRegistered Senior Member

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Gravitational waves travel at the speed of light.
So it disappears at speed of light. I think that when the black hole converted into energy(theoriticaly) then it will not emit gravitational waves but gravitatonal wave will be detected at point B after 10 seconds, when the black hole is converted into energy.

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The following famous statement says it all....
"Spacetime tells matter how to move; matter tells spacetime how to curve"
Gravity is spacetime albeit curved,warped, twisted or GW's

Gravitational waves are a result of catastrophic collisions, assymetric S/N explosions, or any other violent catastrophic event.
And lone BH would generally be spinning and creating a twisting of spacetime [Lense Thirring effect]
https://www.ligo.caltech.edu/page/gw-sources
Sources and Types of Gravitational Waves
Any object with mass that accelerates (which in science means changes position at a variable rate, and includes spinning and orbiting objects) produces gravitational waves, including humans and cars and airplanes etc. But the gravitational waves made by us here on Earth are much too small to detect. In fact, it isn’t even remotely possible to build a machine that can spin an object fast enough to produce a detectible gravitational wave – even the world’s strongest materials would fly apart at the rotation speeds such a machine would require.

Since we can’t generate detectable gravitational waves on Earth, the only way to study them is to look to the places in the Universe where they are generated by nature. The Universe is filled with incredibly massive objects that undergo rapid accelerations (things like black holes, neutron stars, and stars at the ends of their lives). In order to understand the types of gravitational waves these objects may produce, LIGO scientists have defined four categories of gravitational waves, each with a unique “fingerprint” or characteristic vibrational signature that the interferometers can sense and that researchers look for in LIGO’s data. These categories are: Continuous Gravitational Waves, Compact Binary Inspiral Gravitational Waves, Stochastic Gravitational Waves, and Burst Gravitational Waves. Each of these kinds of gravitational-wave generators is described below.

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8. ### danshawenValued Senior Member

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paddoboy's comment is right on track. After detector sensitivity is upgraded before the next run, other types of gravity waves may also be detectable in the categories mentioned, and I wouldn't rule out the possibility of a few other surprises in gravitational astronomy as well. Nature has a way of catching us by surprise as new observational tools and techniques become available. Color me already surprised and delighted that the first run worked so well.

Seeing what a supernova event looks like gravitationally for instance is one thing I think it is safe to say we are all breathlessly waiting and hoping to see. In whatever is left of our all-too-brief lifespans, even better.

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9. ### originIn a democracy you deserve the leaders you elect.Valued Senior Member

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First of all l think you mean a gravitational field not a gravitational wave. So for instance if the sun were to magically vanish the earth would still remain in orbit around the spot that the sun use to exist for about 8.5 minutes, until the change in the gravitational field reached earth. At that point your whole afternoon would be ruined, as we spun off into deep space.

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10. ### ajantaRegistered Senior Member

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But now I have a problem about pair production. I uploaded this file from Google and here electron or positron has mass of 0.511MeV so the energy of the gamma photon must be equal to 2 (0.511)MeV

But electron and positron have gravitatonal field, so the field has come from what energy ?

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11. ### originIn a democracy you deserve the leaders you elect.Valued Senior Member

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According to General Relativity the presence of mass distorts space, it is not using energy to 'make' the field. It is analogous to an electron which as a charged particle produces an electric field, the electron does not lose energy to maintain the field.

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12. ### danshawenValued Senior Member

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Part of the energy of gravity evidently comes from the vacuum surrounding concentrations of mass/energy. No apparent physical contact is necessary for a gravitational field surrounding a concentration of bound energy to give it a push toward its center of mass/energy. It's not as if it were like knocking over a row of dominoes. There doesn't seem to be anything in between. Or isn't there? There is something satisfying about the way dominoes fall, isn't there? They sort of rotate as they fall, each one passing a little of its own rotational energy on to the next domino. Why can't gravity work something like that? Dominoes won't even fall the way they do without gravity.

In isotopic empty space without energy in its bound or unbound non virtual forms, there is no gravity nor any tendency for something to prefer moving in any particular direction. Energy may still be present under such conditions, but it exerts no net force on anything because all of the quantum spins are both entangled and balanced everywhere. You finish the idea. Hint: can spin be exchanged for linear motion or inertia without violating Newton's third law? How? Don't discount any rotational inertia THAT MAY ALREADY BE PRESENT EVERYWHERE. And remember, you can't make a perpetual motion machine using gravity. Sooner or later, the dominoes stop falling.

Last edited: Oct 30, 2016
13. ### quantum_waveContemplating the "as yet" unknownValued Senior Member

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Yes, that is very true.
I would word that differently. The individual gravitational wave passes the point of observation and continues on; some say that gravitational waves might have an infinite reach, but at least they continue to exist well beyond the point of initial observation.
If you are proposing a thought experiment where a black hole finally emits its last energy in the form of a gravitational wave, and therefore ceases to exist locally, the final gravitational wave will continue to exist and will continue to traverse space, and can be detected even after the black hole itself is gone, then yes, that is consistent with the standard model.

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14. ### danshawenValued Senior Member

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And since there are no sources or sinks of gravity like there seems to be for electric charge, when such an object disappears into a singularity, all of the forces associated with the BH disappear as though it never existed. Where does all of the energy go when all of those force pairs of gravitons interacting with matter SUPPORTED BY THE STANDARD MODEL go away? Talking about a perpetual motion (and nonsense) machine, the SM itself is one without the Higgs mechanism to save it. There is a penalty for a model that does not integrate the energy associated with quantum spin dynamics with linear energy propagation or transfer events. There is no scaffolding for this science. It is inconsistent from its inception.

Only time dilation and the energy associated with quantum entanglement keeps black holes and everything else from spontaneously winking out of existence.

Last edited: Oct 30, 2016
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15. ### danshawenValued Senior Member

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It is probably also the weak coupling between quantum spin and linear propagation of energy that explains the hierarchy of forces problem, but I don't claim to understand the mechanism. There are lots of candidate mechanisms to try and perform experiments here, and lots of couplings to measure.

Thank goodness GR worked so well as a first approximation. It got us a very long way toward a better solution.

Last edited: Oct 31, 2016
16. ### ajantaRegistered Senior Member

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Actually when I found that some solar mass is converted into gravitatonal waves about super massive black hole then I thought gravitatonal field of mass is made of mass/energy.

17. ### ajantaRegistered Senior Member

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Electron–positron annihilation occurs when an electron (
e−
) and a positron (
e+
, the electron's antiparticle) collide. The result of the collision at low energies is the annihilation of the electron and positron, and the creation of gamma ray photons.

I know that when a matter comes in gravitatonal field then it feels attraction and it moves.

When an electron and a positron collide then they converted into energy but their ( electron and positron) gravitatonal field exists until they converted into energy, so their gravitatonal field disappear at light speed after they converted...that I think

Now I wanna say when their gravitatonal field disappear at light speed but not in 0 second, and then matter should feel attraction in their gravitatonal field(which is disappearing at light speed) and the matter should move.....so now what about conservation of energy ? Thanks.

Last edited: Oct 31, 2016
18. ### quantum_waveContemplating the "as yet" unknownValued Senior Member

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The thing about the General Science and Technology sub-forum, where you are conducting this thread, is that you can raise questions all you want, but science many not yet have the answers. Members who spend their time on speculations and hypotheses in areas that science has not yet reached a consensus on are not at liberty to speculate in this sub-forum.

19. ### originIn a democracy you deserve the leaders you elect.Valued Senior Member

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As I said there is a difference between a graviational field and gravitational waves. Energy is not continually expended to maintain a gravitational field. Energy IS needed to produce graviational waves.
A VERY loose analogy is a piece of wood in water. The wood will displace a certain amount of water. It does not take energy to maintain the displacement. To make waves in the water you must put energy into the piece of wood, such as a cyclical force to bob the wood up and down in the water.

20. ### originIn a democracy you deserve the leaders you elect.Valued Senior Member

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OK
That is not quite right. The (increadibly slight) warpage of space from an electron and positron will be exactly the same as the warpage from the resulting annihilation photons. Both energy and mass have a gravitational effect.
As I said the graviational field does not disappear. The energy of the e-/e+ and the gamma rays are the same so energy is conserved.

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21. ### ajantaRegistered Senior Member

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My main mistake is...I was thinking that mass is the gravitational charge. ... But a photon can generate a gravitational field because it has energy, which is the gravitational charge.
So I was wrong about that. Thank you all.

22. ### originIn a democracy you deserve the leaders you elect.Valued Senior Member

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Gravitational charge? What is that?

23. ### ajantaRegistered Senior Member

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611
That was my mistake.