Weak field approximation in a model of de Sitter gravity: Schwarzschild solutions and galactic rotation curves

TL;DR

This paper explores weak field solutions in a de Sitter gravity model, showing the existence of Schwarzschild-like solutions and potential explanations for galactic rotation curves without dark matter.

Contribution

It demonstrates the existence of weak Schwarzschild solutions and galactic rotation curve solutions within a de Sitter gravity framework, differing from general relativity.

Findings

Existence of weak Schwarzschild solutions connecting to Newtonian gravity.

Solutions that explain galactic rotation curves without dark matter.

Determination of the coupling constant value.

Abstract

Weak field approximate solutions in the Lambda-->0 limit of a model of de Sitter gravity have been presented in the static and spherically symmetric case. Although the model looks different from general relativity, among those solutions, there still exist the weak Schwarzschild fields with the smooth connection to regular internal solutions obeying the Newtonian gravitational law. The existence of such solutions would determine the value of the coupling constant, which is different from that of the previous literature. Moreover, there also exist solutions that could deduce the galactic rotation curves without invoking dark matter.