Reinterpreting MOND: coupling of Einsteinian gravity and spin of cosmic neutrinos?

TL;DR

This paper proposes that neutrino spin-gravity coupling creates a dark fluid influencing galaxy rotation, linking MOND phenomenology with relativistic neutrino pressure without altering Einstein's gravity.

Contribution

It introduces a novel model where neutrino spin-gravity interactions produce a dark fluid that explains galaxy rotation curves and MOND phenomenology within Einsteinian gravity.

Findings

Neutrino spin-gravity coupling can generate a cosmic dark fluid.

The model reproduces the Tully-Fisher-Milgrom relation.

Dark fluid's internal energy varies with local acceleration.

Abstract

Several rare coincidences of scales in standard particle physics are needed to explain (i) why neutrinos have mass, (ii) why the negative pressure of the cosmological dark energy (DE) coincides with the positive pressure of random motion of dark matter (DM) in bright galaxies, (iii) why Dark Matter in galaxies seems to have a finite phase-space density, and to follow the Tully-Fisher-Milgrom relation of galaxy rotation curves. The old idea of self-interacting DM is given a new spin: we propose that the neutrino spin-gravity coupling could lead to a cosmic neutrino dark fluid with a an internal energy density varying as function of the local acceleration of the neutrino fluid with respect the CMB background. We link the Tully-Fisher-Milgrom relation of spiral galaxies (or MOND) with the relativistic pressure of the neutrino dark fluid without modifying Einsteinian gravity.