TITLE:
Light-Cone Coordinate System in General Relativity
AUTHORS:
Yingqiu Gu
KEYWORDS:
Light-Cone, Null Gradient Field, Coordinate Transformation, Geodesic, Einstein’s Field Equation
JOURNAL NAME:
Journal of High Energy Physics, Gravitation and Cosmology,
Vol.8 No.2,
March
16,
2022
ABSTRACT: If there exists a null gradient field in 3 + 1 dimensional space-time, we can set up a kind of light-cone coordinate system in the space-time. In such coordinate system, the metric takes a simple form, which is helpful for simplifying and solving the Einstein’s field equation. This light-cone coordinate system has wonderful properties and has been used widely in astrophysics to calculate parameters. We discuss the structure of space-time with light-cone coordinate system in detail. We show how to construct the light-cone coordinate system and obtain the conditions of its existence, and then explain their geometrical and physical meanings.