English

Recovering modified Newtonian dynamics by changing inertia

Cosmology and Nongalactic Astrophysics 2011-06-01 v3

Abstract

Milgrom's modified Newtonian dynamics (MOND) has done a great job on accounting for the rotation curves of a variety of galaxies by assuming that Newtonian dynamics breaks down for extremely low acceleration typically found in the galactic contexts. This breakdown of Newtonian dynamics may be a result of modified gravity or a manifest of modified inertia. The MOND phenomena are derived here based on three general assumptions: 1) Gravitational mass is conserved; 2) Inverse-square law is applicable at large distance; 3) Inertial mass depends on external gravitational fields. These assumptions not only recover the deep-MOND behaviour, the accelerating expansion of the universe is also a result of these assumptions. Then Lagrangian formulae are developed and it is found that the assumed universal acceleration constant a0 is actually slowly varying by a factor no more than 4. This varying 'constant' is just enough to account for the mass-discrepancy presented in bright clusters.

Keywords

Cite

@article{arxiv.1011.3618,
  title  = {Recovering modified Newtonian dynamics by changing inertia},
  author = {Ling-Jun Wang},
  journal= {arXiv preprint arXiv:1011.3618},
  year   = {2011}
}
R2 v1 2026-06-21T16:44:24.137Z