# Graviton question

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Assuming an empty universe with only 1 sphereical mass. Therefore by newtonian and relativity theories, there are no interactions with (to/from) this sphereical mass whatsoever. Assuming also, that parallel universes have no mass also and have no interaction with the current universe in question. Assume also QM theories are right and gravitons exist.

So in this case, will gravitons essentially 'run out' because it is constantly ejected into space (with the assumption that energy/matter is conserved and graviton is essentially energy/matter; and that the mass of the sphere is finite). Also because there are no other interactions with other forms of mass and energy in our example, there will be no scattering to return the gravitons back to the original mass. So what happens

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I'm no expert, but i would have thought that gravitons stay as they are.

Gravitons are exchange particles, if there is nothing to exchange these with then they'd just stay in the original mass so to speak. Right?

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If they are like you say then I have other questions. Why is it that gravitons only interact with other masses if there are other masses? It seems like there is another mechanism in play then or some sort of intelligence/response mechanism.

It seems like, if gravitons are the most fundamental of gravity, the only way it can work is if gravitons are constantly being ejected out of the mass - because this way the system is a physical mechanical system through which how gravity works.

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gravitons are virtual particles.

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Gravitational radiation is always being radiated by a source, it doesn't matter if there's nothing for them to interact with, well as long as the source isn't spherically symmetric (or there's some other condition that means it won't radiate). You can have a free graviton, just as one could have a free photon. It'll have been created somewhere in practice, but in calculation it's acceptable to suppose that one can have an exchange particle not attached to two vertices (an external gauge particle).

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Would gravitons actually carry energy away from the source? If they did one would thinkwe would have noticed thses effects long ago.

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Here is a related question I had a while back.
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'']Would gravitons actually carry energy away from the source? If they did one would thinkwe would have noticed thses effects long ago.

Yes they do, but it's not much, and the luminosity is pretty small in any case. Gravitational radiation propogates at c and is very weak, so we have to sit around for a while and wait for a big enough quasar or whatever to shoot some gravitational radiation our way. This is the whole point of LIGO.

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Yea, so in an empty universe, the mass will ultimately run out of gravity after a certain amount of time because they run out of gravitons? Someone still needs to answer this.

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Yea, so in an empty universe, the mass will ultimately run out of gravity after a certain amount of time because they run out of gravitons? Someone still needs to answer this.

Gravitons do not run out. Thats like saying light runs out.

If your in an empty universe there will be no gravitons anyway so I'm not shure I understand what you are asking.

Cheers,

Ryan Jones

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Ok, yea thats what I want answered but you answered indirectly. So gravitons only exist with the existance of other masses. Therefore in a universe with only 1 mass, no gravitons will exist.

However, then can someone explain to me the mechanism through which the masses knows only to respond by ejecting gravitons with the existance of other masses in the universe?

It seems like that for a non intellligent and the most fundamental mechanism of graivty, that the only possible way is for gravitons to be constantly ejected out of the mass instead of only ejecting when there are other masses for interaction in the universe. I know that gravitons are merely used for calculation purposes, but that would seems to show flaws in the system?

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Ok' date=' yea thats what I want answered but you answered indirectly. So gravitons only exist with the existance of other masses. Therefore in a universe with only 1 mass, no gravitons will exist.

However, then can someone explain to me the mechanism through which the masses knows only to respond by ejecting gravitons with the existance of other masses in the universe?

It seems like that for a non intellligent and the most fundamental mechanism of graivty, that the only possible way is for gravitons to be constantly ejected out of the mass instead of only ejecting when there are other masses for interaction in the universe. I know that gravitons are merely used for calculation purposes, but that would seems to show flaws in the system?[/quote']

How about this approach: A force carrier is the unit of actual energy which resolves differences in potential energy between two points. A point source of energy without an opposite, will nevertheless create a field of strain, which will be unresolved. Consider a single point of electrical potential. For a an electron to be created, a pair-point of opposite charge must be present. No pair-point, no electron. Consider the properties of any single particle in isolation? Just idle speculation?

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Assuming an empty universe with only 1 sphereical mass. Therefore by newtonian and relativity theories' date=' there are no interactions with (to/from) this sphereical mass whatsoever. Assuming also, that parallel universes have no mass also and have no interaction with the current universe in question. Assume also QM theories are right and gravitons exist.

So in this case, will gravitons essentially 'run out' because it is constantly ejected into space (with the assumption that energy/matter is conserved and graviton is essentially energy/matter; and that the mass of the sphere is finite). Also because there are no other interactions with other forms of mass and energy in our example, there will be no scattering to return the gravitons back to the original mass. So what happens[/quote']

Where does this single particle live? (I am assuming it is a single particle other wise you have gravitational interactions between the particles in the mass, and the question becomes rather moot.)

It lives in the vacuum where other particles are being created and destroyed all the time. Therfore the particle will interact gravitationally with these other particles. (In fact the same argument is true for electromagnetism too.)

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It lives in the vacuum where other particles are being created and destroyed all the time. .)

Is this proven, or an assumption to which our present mathematical model leads us? You believe in zero point energy as proven fact?

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It's a result of quantum field theory, and there are many reasons why physics accepts the field theoretic approach to particle interactions.

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I suppose someone ought to point out that we don't even know that there is such a thing as a "graviton," and that actually confirming or denying their existence is probably fundamentally impossible. LIGO is supposed to detect gravity waves. The assumption that gravity, like light, behaves like both a wave and a particle is untestable and based on nothing more than some vague notion that different entities ought to be as similar as possible. [/annoying nitpick]

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Yes they do, but it's not much, and the luminosity is pretty small in any case. Gravitational radiation propogates at c and is very weak, so we have to sit around for a while and wait for a big enough quasar or whatever to shoot some gravitational radiation our way. This is the whole point of LIGO.

Woah woah woah. LIGO is designed to test gravitational waves. Gravitons are the supposed force carries of gravity. So anything with mass would emit gravitons, while only an accelerating mass would emit gravitational waves. The waves have energy, its the gravitons that I'm not sure about. Although I still doubt it.

And we will likely detect gravitational waves from something like neutron stars colliding, or black holes eating a huge mass very quickly. Quasars arn't likely to be a source of much gravitational radiation, especially since they're so far away we wouldn't be able to detect it anyway.

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i heard there is a zero gravity on the centre of earth

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i heard there is a zero gravity on the centre of earth

...a little of topic, but yes. Well, at the very center there is no gravity from earth, there would still be tiny amounts from the moon, sun and other bodies. So effectively zero.

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Is this proven, or an assumption to which our present mathematical model leads us? You believe in zero point energy as proven fact?

Yes, it is proven.

Woah woah woah. LIGO is designed to test gravitational waves. Gravitons are the supposed force carries of gravity. So anything with mass would emit gravitons' date=' while only an accelerating mass would emit gravitational waves. The waves have energy, its the gravitons that I'm not sure about. Although I still doubt it.

[/quote']

If the theories are correct, then gravitational waves are gravitons. There is no difference, just as electromagnetic waves are photons.

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I was making a hypothetical situation, just so I can gather the info I wanted to know about gravitons.

I am well aware that gravitons are not proven to exist yet. My topic is just to accept the null hypothesis and the discussion as if it were true so that I can support/objectify on the theory. Seeing how this goes Id prob be better off researching myself since Im new to quantium mechanics.

So ill ask again then. Will gravitons of a mass essentially run out in an empty universe (with only that one mass + no interactions with other universes/branes/etc). Do graivtons constatnly get ejected out of the mass? If so then why doesnt it run out? If not then explain to me where it aquires the 'intelligence' or response mechanism to only eject gravitons when there are mass interactions? Perhaps then the theory is either not as concrete or is incomplete/not fundamental to gravity

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