Yang's gravitational theory

TL;DR

This paper explores Yang's gravitational theory, a gauge-theoretic generalization of Einstein's equations, analyzing its properties, comparing it with Einstein's theory, and discussing the initial value problem.

Contribution

It provides a comprehensive analysis of Yang's gravitational equations, including their properties, comparison with Einstein's equations, and initial value problem insights.

Findings

Yang's equations generalize Einstein's gravitational equations.

Comparison reveals similarities and differences with Einstein's theory.

Initial value problem is well-posed under certain conditions.

Abstract

Yang's pure space equations (C.N. Yang, Phys. Rev. Lett. v.33, p.445 (1974)) generalize Einstein's gravitational equations, while coming from gauge theory. We study these equations from a number of vantage points: summarizing the work done previously, comparing them with the Einstein equations and investigating their properties. In particular, the initial value problem is discussed and a number of results are presented for these equations with common energy-momentum tensors.