Lightlike simultaneity, comoving observers and distances in general relativity

JOURNAL OF GEOMETRY AND PHYSICS

卷:56

Article

Bolós, VJ

关键词: comoving observers;    distance;    simultaneity;    Doppler;    gravitational redshift;   

DOI  :  10.1016/j.geomphys.2005.05.001

来源: Elsevier

【 摘 要 】

We state a condition for an observer to be comoving with another observer in general relativity, based on the concept of lightlike simultaneity. Taking into account this condition, we study relative velocities, Doppler effect and light aberration. We obtain that comoving observers observe the same light ray with the same frequency and direction. and so gravitational redshift effect is a particular case of Doppler effect. We also define a distance between an observer and the events that it observes, called lighttike distance, obtaining geometrical properties. We show that lightlike distance is a particular case of radar distance in the Minkowski space-time and generalizes the proper radial distance in the Schwarzschild space-time. Finally. we show that lightlike distance gives us a new concept of distance in Robertson-Walker space-times, according to Hubble law. (c) 2005 Elsevier B.V. All rights reserved.

【 授权许可】

Free