New Physics at Low Accelerations (MOND): an Alternative to Dark Matter

TL;DR

This paper introduces MOND, a paradigm proposing modifications to physics at low accelerations to explain galactic dynamics without dark matter, highlighting its phenomenology and theoretical frameworks.

Contribution

It presents the MOND paradigm as an alternative to dark matter, connecting galactic acceleration phenomena with cosmic acceleration scales, and reviews both nonrelativistic and relativistic theories.

Findings

MOND explains galaxy rotation curves without dark matter

Acceleration scale in MOND matches cosmic acceleration scales

Comparison shows MOND's phenomenological success against dark matter models

Abstract

I describe the MOND paradigm, which posits a departure from standard physics below a certain acceleration scale. This acceleration as deduced from the dynamics in galaxies is found mysteriously to agree with the cosmic acceleration scales defined by the present day expansion rate and by the density of `dark energy'. I put special emphasis on phenomenology and on critical comparison with the competing paradigm based on classical dynamics plus cold dark matter. I also describe briefly nonrelativistic and relativistic MOND theories.