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zerocold
2010-May-11, 09:06 AM
Ok guys..explain me the [Language]..ahaha,

No, seriously, somebody explain me :whistle:

Given that all energy interchange in force fields is done through virtual photons, then how can virtual photons been interchanged between the photon and the gravity source

I understand some of you will pointing out the space bending...well, i think this is not that relevant for this topic...or is it?..explain me that as well :p

BTW , is the space bending a concept accepted in quantum mechanics?

Strange
2010-May-11, 09:35 AM
We don't have a quantum theory of gravity, so I'm not sure your questions will be answered...


Given that all energy interchange in force fields is done through virtual photons

Not necessarily photons. The type of virtual particle depends on type of the force.


then how can virtual photons been interchanged between the photon and the gravity source

I don't know, but I am guessing this would be mediated by virtual gravitons?

gzhpcu
2010-May-11, 11:31 AM
Ok guys..explain me the [Language] ahaha,

No, seriously, somebody explain me :whistle:

Given that all energy interchange in force fields is done through virtual photons, then how can virtual photons been interchanged between the photon and the gravity source

No. In the standard model, gluons are the force carriers for the strong nuclear force, W & Z bosons are the force carriers for the weak nuclear force, photons are the carriers for the electromagnetic force. The graviton is posited as the force carrier for gravity.


I understand some of you will pointing out the space bending...well, i think this is not that relevant for this topic...or is it?..explain me that as well :p

BTW , is the space bending a concept accepted in quantum mechanics?
Warping of spacetime is proposed by General Relativity, not by Quantum Mechanics.

zerocold
2010-May-11, 11:55 AM
No. In the standard model, gluons are the force carriers for the strong nuclear force, W & Z bosons are the force carriers for the weak nuclear force, photons are the carriers for the electromagnetic force. The graviton is posited as the force carrier for gravity

I understand this, sill all of them must be virtual, since in the force fields there is not free interaction

The bosons are the manifestations of these force carriers when the closed force field is "broken", like virtual photons in a magnetic field turning into free EM-radio photons.


We don't have a quantum theory of gravity, so I'm not sure your questions will be answered...

probably, but there are models for the so called 'graviton' i would like to know how they are based, since the photon is massless, how can something like the graviton been conceptualized?...

Jeff Root
2010-May-11, 10:46 PM
I'm not sure what you are asking, but I'll comment on one aspect
which seems relevant, and possibly central.

Photons are massless. Gravity arises from (to express it vaguely) energy.
So a collection of photons gives rise to a gravity field. But two things:
First, you could never have enough photons in a small enough volume to
have a detectible amount of gravity. Second, the gravity of a collection
of photons would only be theoretically detectible if the photons are moving
in different directions relative to the observer. A sphere of totally incoherent
photons moving every which-way permits a relatively simple mathematical
description. You might find more by searching for "equivalent mass".

-- Jeff, in Minneapolis