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arXiv · 2410.04388

On the transverse-traceless gauge condition when matters are presented

Yadong Xue·Xiaokai He·Zhoujian Cao
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Abstract

The transverse-traceless gauge condition is an important concept in the theory of gravitational wave. It is well known that vacuum is one of the key conditions to guarantee the existence of the transverse-traceless gauge. Although it is thin, interstellar medium is ubiquitous in the universe. Therefore, it is important to understand the concept of gravitational wave when matter is presented. Bondi-Metzner-Sachs theory has solved the gauge problem related to gravitational wave. But it does not help with the cases when gravitational wave propagates in matters. This paper discusses possible extensions of the transverse-traceless gauge condition to Minkowski perturbation with matter presented.

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Yadong Xue, Xiaokai He, Zhoujian Cao. 2024-10-06. On the transverse-traceless gauge condition when matters are presented. https://arxiv.org/abs/2410.04388

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