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Would gravitons themselves experience time dilation?

QuoteWould gravitons themselves experience time dilation?If gravitons exist, and they travel slower than the speed of light, then they would experience time dilation. However, there is thought to be only one type of spin 2 boson (the graviton), so it is not clear how this time dilation would show itself - perhaps by decay of the graviton over cosmological distances?If the graviton is massless (as is currently thought), then it would have an infinite range and not change with distance (until it interacts with a mass). Time has no meaning for such a particle.

If we consider two frames of reference where one is time dilated significantly more than the other and an observer in each measures the speed of light they will both agree. However if you could directly compare the two the photon in the slower frame would appear slower to the observer in the faster frame. That is: light is slowed by gravitation.

If the graviton does not experience this same effect then it is effectively superluminal in its velocity for any time dilated observers.

Quote from: jeffreyH on 24/08/2014 13:24:16If we consider two frames of reference where one is time dilated significantly more than the other and an observer in each measures the speed of light they will both agree. However if you could directly compare the two the photon in the slower frame would appear slower to the observer in the faster frame. That is: light is slowed by gravitation.Good stuff Jeffrey. IMHO the "God's eye view" is the way to understand it. Quote from: jeffreyH on 24/08/2014 13:24:16If the graviton does not experience this same effect then it is effectively superluminal in its velocity for any time dilated observers.The graviton remains hypothetical. But note that the photon "conveys inertia between the emitting and absorbing bodies". It has a zero rest mass but a non-zero inertial mass, and a non-zero active gravitational mass. And it isn't surrounded by a cloud of gravitons. Instead it's the only particle there. So in a way, a photon is a graviton. IMHO it's a pity the name ...sorry, you cannot view external links. To see them, please REGISTER or LOGIN has been taken.

I don't know the answer to this, and it seems as if no one on the forum can do more than speculate (myself included), but it's worth pointing out that gravitational time dilation is a consequence of the general theory of relativity, which is a classical field theory. Particles such as the graviton come from quantizing the classical field theory and so they should be able to explain how to build the classical theory from more fundamental, quantum building blocks.For example, the properties of the electromagnetic field arise from photons.So since time dilation as its currently understood is a consequence of general relativity and gravitons should explain how to build general relativity from particles, a graviton theory should probably explain how time dilation comes to be as a result of fundamental particles. And although we know some properties that a graviton theory has to satisfy, there is no accepted theory of a graviton yet...

You might say it is a matter of taste. I prefer my universe as simple as possible, and hope that it agrees with me. but I can't guarantee it, so your approach might be the way it is, although I'm unsure on what you consider your point of reference there?there's no theory or hypothesis that can't be adjusted That's the beauty of science.

Quote from: JP on 27/08/2014 14:51:34I don't know the answer to this, and it seems as if no one on the forum can do more than speculate (myself included), but it's worth pointing out that gravitational time dilation is a consequence of the general theory of relativity, which is a classical field theory. Particles such as the graviton come from quantizing the classical field theory and so they should be able to explain how to build the classical theory from more fundamental, quantum building blocks.For example, the properties of the electromagnetic field arise from photons.So since time dilation as its currently understood is a consequence of general relativity and gravitons should explain how to build general relativity from particles, a graviton theory should probably explain how time dilation comes to be as a result of fundamental particles. And although we know some properties that a graviton theory has to satisfy, there is no accepted theory of a graviton yet...There have been proposals that the graviton should exceed c. I doubt that. However there may be more to that point of view than meets the eye. At the moment I am grappling with the Maxwell equations very badly. Better people than me have attempted such things. I'll keep going simply because I love a mystery and you learn an awful lot on the way. Mathematics never ceases to amaze me.

Quote from: jeffreyH on 27/08/2014 23:52:25Quote from: JP on 27/08/2014 14:51:34I don't know the answer to this, and it seems as if no one on the forum can do more than speculate (myself included), but it's worth pointing out that gravitational time dilation is a consequence of the general theory of relativity, which is a classical field theory. Particles such as the graviton come from quantizing the classical field theory and so they should be able to explain how to build the classical theory from more fundamental, quantum building blocks.For example, the properties of the electromagnetic field arise from photons.So since time dilation as its currently understood is a consequence of general relativity and gravitons should explain how to build general relativity from particles, a graviton theory should probably explain how time dilation comes to be as a result of fundamental particles. And although we know some properties that a graviton theory has to satisfy, there is no accepted theory of a graviton yet...There have been proposals that the graviton should exceed c. I doubt that. However there may be more to that point of view than meets the eye. At the moment I am grappling with the Maxwell equations very badly. Better people than me have attempted such things. I'll keep going simply because I love a mystery and you learn an awful lot on the way. Mathematics never ceases to amaze me.While I can't help you much with Einstein's field equations and gravitons, I am an expert in Maxwell's equations should you have any questions.

I have to politely disagree with this viewpoint...

Quote from: jeffreyH on 27/08/2014 01:52:38I have to politely disagree with this viewpoint...Noted Jeffrey. Perhaps another tack you could take is whether gravitons get out of a black hole. That might tell you that the graviton is a virtual particle and a field quantum. A "chunk of field" as it were, rather than a real particle that moves from A to B. pmb: noted! It's good to talk. Sometimes people disagree, but if we didn't, life would be so dull.

I remember reading somewhere that if you reach the speed of light then time stops completely. I always wondered what that meant, for if light experiences no time then how could it move in time?light moves at a certain speed (the speed of light) it travels faster then any thing but how can it move at all if it takes time to move? Could light exist in time but not experience time? Who knows how that works?I guess the answer to your question is that if gravitons do exist and travel at light speed then gravitons would experience no time, if they travel a little slower then they would experience time dilation.