quantum gravity concept

[ydoaPs]

say mass doesn't directly bend spacetime. say the graviton is what actually bends spacetime. massive particles just emit gravitons. the farther the gravitons get from the source, the more spread out they are, therefore the force is weaker (which makes sense, with the inverse-square law). gravitons don't need to be absorbed, they just are emmitted. i am guessing the mass would determine the graviton emmission rate. i wouldn't even know how to start making equations to compare to gr. i don't even know how to do tensor calculus, so i couldn't compare with gr if i had the equations. there is probably some qm stuff that i need to factor in. this is just a base idea for now. in the diagram, there are two objects with different masses. the green lines are graviton paths.

[5614]

Gravitons could/would be absorbed because otherwise gravity would become stronger over time as more and more gravitons come into existence, also that would be how they interact.

 

Obviously QG (quantum gravity) isn't a real theory yet as there's, so far, no solid proof, although for a "theory" which doesn't exist its quite popular!

[ydoaPs]

if you look at the sun, does it get brighter? it continually emits photons.

[5614]

That's not what I meant... if gravitons were continually emitted and never absorbed then originally there were no gravitons (before big bang) then there would have been the first ever graviton... then the second... the universe would be continually "filling up" with gravitons.

[ydoaPs]

no, they go on and on infinitely.

[DQW]

Please look up "exchange particles"... and note the use of the word 'exchange'.

[ydoaPs]

gravitons don't have to "exchange" for gravity to work.

[5614]

So the QG theory which is not yet certain in any way is certainly working in this way?

 

Every other force; Strong/weak/EM have exchange particles, the quantization of gravity is supposed to work in the same way as the other forces.... ie. a carrier particle which is an exchange particle.

[ydoaPs]

yes. in this model-under-production, gravitons don't act on matter, they act on space.

[DQW]

gravitons don't have to "exchange" for gravity to work.

If by "for gravity to work" you mean "for a pair of particles to influence each other's state" (described by a Lagrangian, say), then I'm not sure how your statement can be true.

 

However, this is not something I'm terribly familiar with, other than knowing that QG was itself abandoned because it was not renormalizable. I think higher than second order corrections led to divergences that no one could make go away (at least, not until LQG came along). In any case, I think QG was abandoned when string theories came along that would be renormalizable, and they predicted a spin 2 massless boson !

 

Now, however, LQG seems to be quite hot.