Spacetime symmetries and Kepler's third law

作者:Le Tiec Alexandre*
来源:Classical and Quantum Gravity, 2012, 29(21): 217002.
DOI:10.1088/0264-9381/29/21/217002

摘要

The curved spacetime geometry of a system of two point masses moving on a circular orbit has a helical symmetry. We show how Kepler's third law for circular motion, and its generalization in post-Newtonian theory, can be recovered from a simple, covariant condition on the norm of the associated helical Killing vector field. This unusual derivation can be used to illustrate some concepts of prime importance in a general relativity course, including those of Killing field, covariance, coordinate dependence and gravitational redshift.

  • 出版日期2012-11-7