Scalar-field solutions

If Milgrom doesn't work, then what? A few more papers have come in over the weekend concerning non-CDM solutions to various problems we got. I needed a few more days on this one.

One paper last Friday fingers exactly Milgrom, to resolve the Hubble Tension, of that constant there named Hubble-Lemaître. I do wish the press-release had pressed the authors harder against Milgrom.

Overall (h/t Turtle) Tonatiuh Matos, Luis A. Ureña-López, and Jae-Weon Lee offer a fresh summary of the non-CDM, er... "field". (Pun not intended.) Where Milgrom dared modify Newton, these theories would modify Einstein. They have in common, to introduce a scalar field, like the Higgs. Milgrom actually turns out to be one solution to the problems engaged in the scalar-field models, so those models don't rule Milgrom out. (The data rule Milgrom out; again, this paper doesn't engage all that...)

Johanan Moffat wears his "MOG" on his sleeve. MOG would add to general-relativity, two gravitational degrees of freedom. First, the gravitational coupling G would no longer be constant; it would be 1/χ where χ is his scalar field. The second-up is a new vector field, φ_μ. This is the bit I don't understand: The gravitational coupling of the vector field to matter is universal with the gravitational charge Q_g.

Apparently Moffat's two new fields don't fail the wide-angle low-mass test. Moffat insists, in lieu of "a₀", the system size and length size scale. Other theories should likewise stand or fall on that test. But how does Moffat do against Hubble-Lemaître?

And we still have questions about mass itself. Does the χ field relate to the Higgs field? If not, where are the χ bosons? What to say of axions, neutrinos... gravitons?