Once more - Dark Matter takes a serious hit

[Dennis P Brown]

An observation that invalidates many dark matter concepts. And, of course, supports that 'gravity' appears as a "1/r" 'force' rather than a "1/r^2" 'force' in galaxy rotation speeds with distance from the center. This, I feel is easy to reconcile using quantum mechanics to explain gravity and general relativity isn't even required. But that is another story.

See: https://www.youtube.com/watch?v=TfHzRfADe1k

Again, Dr. Hossenfelder talks about the paper

[Rich Gorski]

It will be difficult for me to accept the MOND concept where the effect of gravity reduces from 1/r^2 to 1/r at galactic distances. At least 1/r^2 has its basis in geometry where the surface area of a sphere goes as 1/r^2 so the flux of anything through a spherical surface, photons, particles, gravitons... also goes as 1/r^2. Has anyone in the MOND arena presented a mechanism for this change from 1/r^2 to 1/r?

Rich G.

[Dennis P Brown]

If gravity is an effect of space and time, and not photons, then the '1/r^2' is irrelevant and not needed (through it certainly works that way around Sol!) I do agree that if gravity is a photon, then that would be the case - extremely hard to get around that if it was the case, as you point out.

General Relativity (GR) makes gravity an effect of space-time so since that theory holds in all known experiments to extreme precision, that currently rules. The standard model does not support a graviton so a photon of gravity is neither needed or even possible under that theory.

No one currently publishing on MOND has offered any viable method* (other then just writing the equation - lol) for how that transition occurs or ever could from a physical methodology. Nor how to address the issue relative to GR, at all.

I have been working on one and it is certainly coming together. It uses quantum effects (solely) to create 'space curvature' (in a physical sense of the word) and does require a '1/r^2' effect for stars (locally) but provides a '1/r' effect for galaxies. It also address/explains expansion and fixes the rather terrible "total energy" problem that field theory chokes on. Not really all that complex concepts are required nor any special/new physics and is fully based in GR and known experimental data. Still a lot to do but if all goes well, next HEAS I will present the basic theory.

* There are other approaches/ideas that do give explanations for their theories but these do not really explain either gravity nor fit observations enough to be considered viable alternatives. So, I tend to ignore them as fringe at best. Only Dark Matter or MOND have any real explanation for observational data to date. In this paper and many other observations recently, Dark Matter fails badly. MOND has, to date, provided the best fit to the most data w/o contradiction. But it too has issues besides no physical explanation/bases and the ad hoc creation of the proper distance fall off effect is hardly a theory.

[Rich Gorski]

Interesting discussion.

If the plan is to quantize gravity (I think most researches are) then a exchange particle is necessary and should be massless and move at the speed of light. It's interesting that gravitational waves move at speed = c. If there were no exchange particle and only a "curvature of spacetime" would speed of gravitational waves still be limited to speed = c? My understanding of spacetime is that it is not limited by the speed of light and can move as fast as it wants... as some galaxies are doing due to the expansion of space (best estimate = 73.3 kilometers per second per megaparsec). So galaxies at a distance of 4092 megaparces (13.3 billion lightyears) should be exceeding away from us faster than light and I guess we will never see them or be influenced by them in any way.

Rich G.

[Dennis P Brown]

Space-time curvature as per General Relativity (GR) has no innate speed (it is not a photon). However, its effects must be identical to the speed of light or this we would be detected. Ditto, it can't be faster, either. Through I can't prove this off the top of my head; but certainly binary's would, I'd think, have issues.

Using quantum effects does impose a finite volume/time unit according to quantization (yes, a duh there-lol.) However, since there is no quanta of gravity (per my approch and certainly by GR) this is just not relevant. Entanglement does come into play, and in fact, as far as GR is concerned is considered vital for time/gravity effects.

As you know, entanglement is not restricted by the speed of light (c) but that is an area that is often confused by many speakers (here I blame physicist who are sloppy.) Entanglement does not exceed 'c' despite the many claims by many speakers. This is solely because they want to keep it simple (due to a miss-understanding on what entanglement means.) Its purely a wave interaction that is encoded in the complex waves themselves - a math entity with an imaginary value (phase) - and hence, can not be observed until wave collapse - i.e. measurement (the imaginary value is removed.) So when density wave collapse occurs many light years away the information of the state is still there and now measured. Yes, both systems will have the related measurement (I.e. if one is spin up, the other will be spin down). It wasn't due to faster than light travel. BUT (and there is the issue) the encoding is not available until measurement because its contained in the imaginary part of the function. This concept can not be conveyed to the public (really, imaginary functions? lol) so instead, it is considered an instantaneous reaction to avoid that rather strange statement - i.e. math. There's a bit more, of course, but that is the main parts.

Quantizing gravity does not have anything to do with a photon of gravity (not required IMO and certainly is not needed by GR) so the standard model does not come into play nor will an exchange particle/force carrier be required directly. So the issue of 'c' is a red herring for this approch.

We still 'see' galaxies moving faster than light (for now) that are very far away (these are many billions of light years - something like 43 billion light years distant) but that is due to space increasing with time. Yes, that is solely due to the space (as you mention) stretching (that makes the galaxy 'appear' it is moving faster than light) but the red shifted photons are still reaching us because those move at 'c' and the galaxy (now) is certainly beyond our event horizon but then, wasn't moving that fast when the photon was released. But looking back in time - 13. 3 billion years is solely limited by the start of the 'big bang' because one is looking back in time and know that is 13.3 billions years ago; those objects (Background microwave photons for instance) are not moving away from us. Different issues there.