This is a very short post about a recent thought on the phenomenology of Modified Newtonian Dynamics MOND.
We have explained MOND in our previous posts, but in short, it is a primitive theory of dynamics with which one can fully explain the rotation of all galaxies without the need for any dark matter and with a single free parameter for all of them. This parameter of a constant acceleration scale, we all think of course it is not fundamental but derived from a complete theory which explains MOND, and this is the key question. Where does MOND come from?
Well, Milgrom himself and as I recently discovered, Pavel Kroupa, who has a great presentation about the problems of the standard model of cosmology and in particular dark matter, both seem to agree that MOND comes from the quantum vacuum as the agent exerting inertia. And I have a problem with this, which I want to point out in this post. What is the evidence we have for MOND having an origin in the quantum vacuum? The only evidence, is that the acceleration constant matches a relationship with the cosmological constant of dark energy. But this cosmological constant is only measured indirectly, and no one knows what dark energy really is, not even if it comes from non-zero energy of the vacuum! In contrast, MOND’s acceleration scale constant matches the gravitational acceleration or field intensity calculated from the mass and observable radius of the universe, and these are directly measured values, although approximately. This points directly to local dynamics being affected by global mass distributions and missing boundary conditions á la Mach. And yet most of the community in MOND prefers the quantum vacuum interpretation. Why is barely no one working on MOND and Mach’s principle?
I searched through the literature and there are very few papers trying to link MOND and Mach’s principle.
And even though I am happy that there were people working on this, their work was so unsatisfactory that I had to write myself a paper about MOND and Mach’s principle which is far more complete than any other work out there. You have the paper available for free in ArXiv, I invite you to read it even if you don’t know about Mach’s principle, because I explain it from the very beginning, and I really hope it inspires the community for alternative explanations of MOND.