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If the massive gravitron was leaving a black hole it would be slowed by the black hole's gravity.

(1) We should see this as some inconsistency in how gravity scales with the mass of a black hole. The larger ones would have proportionately greater 'drag' on leaving gravitrons, pulling more in.

(2) If they are massive, and therefore subject to slowing, shouldn't gravity waves leaving a black hole be subject to some sort of doppler effect? Should we be looking for red/blueshifts in these waves?

(3) If gravitrons have mass and are subject to gravity, what brings that gravity? What sub-gravitron particle regulates gravity going in/to/out of the gravitron? This would require a new set of particles be created by non-gravitron massive objects (ie black holes) alongside the gravitrons. Like I said, too strange to exist.




(None of my points below say the graviton is massless, just that it's not crazy. As another post says, this new observation probably confines the graviton mass to be less than 10^-55 grams)

> If the massive gravitron was leaving a black hole it would be slowed by the black hole's gravity.

A graviton wouldn't be able to escape a black hole. A photon can't, and it's massless. The gravity of a black hole is actually a self-sustaining effect of the curvature of the spacetime around the black hole.

> (1) We should see this as some inconsistency in how gravity scales with the mass of a black hole. The larger ones would have proportionately greater 'drag' on leaving gravitrons.

We don't know details of the gravitational field around black holes and the mass that created it, because none have been observed close up. To an extent, the mass of a black hole is defined by its gravity.

> (2) If they are massive, and therefore subject to slowing, shouldn't gravity waves leaving a black hole be subject to some sort of doppler effect? Should we be looking for red/blueshifts in these waves?

Again, photons are massless and subject to the doppler effect. Gravitons, massless or not, will be too.

> (3) If gravitrons have mass and are subject to gravity, what brings that gravity? What sub-gravitron particle regulates gravity going in/to/out of the gravitron? This would require a new set of particles be created by non-gravitron massive objects (ie black holes) alongside the gravitrons. Like I said, too strange to exist.

Force carying particles can interact with themselves, c.f. gluons in QCD. In fact, GR is a non-linear theory so there will be non-linear interactions (as far as you can describe them in the weak limit).


> A graviton wouldn't be able to escape a black hole ... the curvature of the spacetime around the black hole

But isn't the curvature of spacetime around the black hole supposed to be the effect of its interaction with the graviton??

Is this where the translation from GR -> QM breaks down?


> Is this where the translation from GR -> QM breaks down?

Sort of, to get a graviton you introduce perturbations on a background metric. (Basically small wiggles of spacetime around an 'average.') You don't do anything like that when you solve the Einstein equations. Consequently, the background spacetime ( that is, the black hole) is not really made of gravitons. (At least in some sense.)


So in GR the metric itself is warping, which is a problem if you need a background reference/stable metric to define your graviton field? Is that close? Anyway thanks.


Yes, pretty close.


> We should see this as some inconsistency in how gravity scales with the mass of a black hole.

This inconsistency is a part of general relativity (even though gravitons themselves aren't). A black hole does not follow the GM/r^2 gravity law.

> If they are massive, and therefore subject to slowing, shouldn't gravity waves leaving a black hole be subject to some sort of doppler effect? Should we be looking for red/blueshifts in these waves?

Yes, there is a doppler effect.

> If gravitrons have mass and are subject to gravity, what brings that gravity? What sub-gravitron particle regulates gravity going in/to/out of the gravitron? This would require a new set of particles be created by non-gravitron massive objects (ie black holes) alongside the gravitrons. Like I said, too strange to exist.

Gravitons. Every now and then a pair of gravitons may exchange more gravitons (these are also virtual particles, so it's fine). This is why Feynman diagrams exist, so that you can not only calculate the interaction between two particles through a graviton, but also calculate the contribution of the lower-probability situations where more gravitons magically appear to transmit gravity between gravitons.

This is nothing new. Gluons (the carrier for the color/strong force) do basically the same thing. They are also bound by the force they carry, and thus gluons can interact with each other with more gluons.

Because these are virtual particles and only exist as a probability, this doesn't lead to infinite recursion. The secondary gravitons are improbable, and the tertiary gravitons more so, and so on, and the final series converges.


> and the final series converges.

Or not, and we yell "look behind you!" and then dump the infinities out the window.

https://en.wikipedia.org/wiki/Renormalization


Hah, that too :p

When I first learned about renormalization formally (i.e., with equations) I realized it wasn't that bad. But still, pretty sneaky :P


>(1) We should see this as some inconsistency in how gravity scales with the mass of a black hole. The larger ones would have proportionately greater 'drag' on leaving gravitrons.

Perhaps, no clue how a quantum mechanical gravity would interact with a black hole.

>(2) If they are massive, and therefore subject to slowing, shouldn't gravity waves leaving a black hole be subject to some sort of doppler effect? Should we be looking for red/blueshifts in these waves?

The Doppler effect happens even for light, which isn't massive at all (that we know of).

>(3) If gravitrons have mass and are subject to gravity, what brings that gravity? What sub-gravitron particle regulates gravity going in/to/out of the gravitron?

There's no reason they couldn't interact with themselves, in fact I guess that's probably the most likely case.


If they interact with each other, then wouldn't any "wave" collapse?

The particles leave the event in a smooth wave. Then they run into other waves, or each other, or just the background gravity fields. This perturbation should cause them to clump together. So in short order the smooth wave would become large blobs of gravitrons more akin to raindrops than waves. And without anything holding them apart, might not some of these clumps condense into some sort of ... I don't have the words for such an object. I wouldn't want to get in its way.


I think what you're trying to describe is something like 'confinement'. I'm not confident that a massive graviton will necessarily lead to confinement, neither gravitons nor confinement are that well understood.


It's a converging series; instead of getting a clumping you may get a slight mass increase. These new gravitons that modulate gravity between existing gravitons are not 100% there, so they do not contribute that much.




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