Spacetime orientation and the meaning of Lorentz invariance in general relativity

TL;DR

This paper explores how the concept of spacetime orientation influences the understanding of Lorentz invariance within general relativity, especially considering symmetry violations like parity violation.

Contribution

It introduces the importance of spacetime orientation as a fundamental aspect of the causal structure affecting Lorentz invariance in general relativity.

Findings

Spacetime orientation is crucial for understanding Lorentz invariance.

Parity violation challenges the assumption of full Lorentz invariance.

The causal structure of spacetime incorporates orientation as a key element.

Abstract

The parity violation at the level of weak interactions and other similar discrete symmetries breaking show that the invariance of laws under the full group of Lorentz transformations can not be taken granted. We examine the principle of Lorentz invariance under the general theory of relativity, and demonstrate the importance of a concept of the spacetime orientation as part of the causal structure of spacetime.