Motion of a test body in the presence of an external scalar field which respects the weak equivalence principle

TL;DR

This paper proposes that the rotation curves of spiral galaxies can be explained by the interaction of galactic matter with a light scalar field in general relativity, aligning well with observed data.

Contribution

It introduces a model where a long-range scalar field, respecting the weak equivalence principle, accounts for galaxy rotation curves, providing an alternative to dark matter.

Findings

Good agreement with 23 observed galaxy rotation curves

Scalar field interaction explains rotational dynamics

Supports scalar field as a viable alternative to dark matter

Abstract

It is shown that the main contribution to the rotational curve of a spiral galaxy may be due essentially to the interaction, in the general relativistic spacetime, of the galactic matter with a very light long range scalar field which respects the weak equivalence principle. The comparison of the theoretical results with 23 spiral galaxy rotation curves shows a good agreement between our proposal and observations.