On Thursday, March 24, 2022 at 2:10:27 AM UTC-6, RichA wrote:
> https://phys.org/news/2022-03-massive-gravitons-viable-dark-candidates.html

But things fall down! So at least we know that gravity is real!

And we know that electromagnetism is conveyed by particles called "photons";
this has been proven because of the photoelectric effect.

Thus, it's plausible that gravity is mediated by gravitons.

But gravitons which, unlike photons, have nonzero rest mass?

Well, the strong nuclear force and the weak nuclear force are mediated
by particles with a nonzero rest mass. That's why they're short-range forces,
with exponential decay superimposed on the inverse-square law, giving a
Yukawa potential.

So these hypotheses are at least testable. If the gravitational potential
is a Yukawa potential, the gravitational interaction between galaxies
should be affected, since they're far away from each other.

John Savard

On Monday, March 28, 2022 at 4:54:18 PM UTC-6, RichA wrote:

> So do you think gravitons generate more "pull" than photons exert pressure?

How much pressure a photon exerts depends on its frequency...

John Savard

On 28/03/2022 23:54, RichA wrote:
> On Friday, 25 March 2022 at 10:24:11 UTC-4, Quadibloc wrote:
>> On Thursday, March 24, 2022 at 2:10:27 AM UTC-6, RichA wrote:
>>> https://phys.org/news/2022-03-massive-gravitons-viable-dark-candidates.html
>>
>> But things fall down! So at least we know that gravity is real!
>>
>> And we know that electromagnetism is conveyed by particles called "photons";
>> this has been proven because of the photoelectric effect.

That is a somewhat simplistic way of looking at it. Wave particle
duality of quantum mechanics is much more complicated than that!

All particles can behave as waves or particles with a wavelength that is
related to their momentum. Silver atoms and C60 buckey balls have been
used successfully to do the Young's slit experiment. They have now moved
onto biomolecules and hope soon to diffract an entire virus!

https://iopscience.iop.org/article/10.1088/0031-8949/91/6/063007/meta
>>
>> Thus, it's plausible that gravity is mediated by gravitons.
>>
>> But gravitons which, unlike photons, have nonzero rest mass?
>>
>> Well, the strong nuclear force and the weak nuclear force are mediated
>> by particles with a nonzero rest mass. That's why they're short-range forces,
>> with exponential decay superimposed on the inverse-square law, giving a
>> Yukawa potential.

If there was such an effect at long range I think it would mess up the
stability of what is actually observed and simulations of the early
universe.

>> So these hypotheses are at least testable. If the gravitational potential
>> is a Yukawa potential, the gravitational interaction between galaxies
>> should be affected, since they're far away from each other.
>>
>> John Savard
>
> So do you think gravitons generate more "pull" than photons exert pressure?

Gravity and gravitons to mediate it (if they exist) are insanely weak.
The gravitational constant Big G was ironically named! The difference to
electromagnetism is that gravity has purely attractive forces.

There is as far as we know in current theories no anti-gravity or
negative masses.

--
Regards,
Martin Brown

On Wednesday, March 30, 2022 at 5:31:08 AM UTC-6, Martin Brown wrote:
> > On Friday, 25 March 2022 at 10:24:11 UTC-4, Quadibloc wrote:

> >> And we know that electromagnetism is conveyed by particles called "photons";
> >> this has been proven because of the photoelectric effect.

> That is a somewhat simplistic way of looking at it. Wave particle
> duality of quantum mechanics is much more complicated than that!

I suppose you could say that, but I lacked the space to attempt a
comprehensive discussion of that, and anyways...

> All particles can behave as waves or particles with a wavelength that is
> related to their momentum. Silver atoms and C60 buckey balls have been
> used successfully to do the Young's slit experiment. They have now moved
> onto biomolecules and hope soon to diffract an entire virus!

Well, then, you're just proving that... even _electron diffraction_ shows that
_despite_ "wave-particle duality", it's as legitimate to say that light is "really"
made up of photons as it is to say that atoms "really" contain electrons!

So if you want to argue that light isn't just a stream of photons, but also has
a wave nature that needs to be seriously taken into account... then you're only
*hurting* your argument by saying that things we undeniably view as being
solid and material, like silver atoms and buckyballs, can also diffract. Because
then the diffraction of light *stops* being an argument for things being more
complicated than light is made out of photons!!!

I mean, it's great to argue physics, but first you need to raise points that work
in the right direction, instead of starting out by shooting yourself in the foot!

John Savard