Relativistic time delay analysis of pulsar signals near ultra-compact objects
arxiv(2024)
摘要
The upcoming discoveries of pulsars orbiting the center of the Milky Way will
present unparalleled opportunities to examine the causal structure of the
spacetime geometry of Sagittarius A*. In this paper, we investigate the fully
relativistic propagation time delay of pulsar signals in the
Joshi-Malafarina-Narayan (JMN-1) and Janis-Newman-Winicour (JNW) spacetimes.
This delay arises basically from the spacetime curvatures in the vicinity of
these ultra-compact objects, induced by the intense gravitational field near
the Galactic Center (GC). Using the principles of gravitational lensing, we
compute the arrival time of photons originating from a pulsar in orbit around
the GC. To validate our approach, we compare our time delay analysis of the
Schwarzschild black hole with the corresponding delay in the post-Newtonian
framework. Subsequently, we find that the propagation time of pulsar signal is
greater and lesser for the given horizon-less ultra-compact objects for direct
and indirect propagation respectively. Therefore, our results suggest quite
significant propagation time delay differences in JMN-1 and JNW spacetimes,
when compared to the Schwarzschild black hole case. This can be inferred as a
possible distinguishing feature for these ultra-compact objects' geometries.
更多查看译文
AI 理解论文
溯源树
样例
生成溯源树,研究论文发展脉络
Chat Paper
正在生成论文摘要