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Comments on the paper by S. Samuel "On the speed of gravity and the Jupiter/Quasar measurement"

Sergei M. Kopeikin
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Abstract

Recent review article by S. Samuel "On the speed of gravity and the Jupiter/Quasar measurement" published in the International Journal of Modern Physics D13, 1753 (2004) provides the reader with a misleading "theory" of the relativistic time delay in general theory of relativity. Furthermore, it misquotes original publications by Kopeikin and Fomalont & Kopeikin related to the measurement of the speed of gravity by VLBI. We summarize the general relativistic principles of the Lorentz-invariant theory of propagation of light in time-dependent gravitational field, derive Lorentz-invariant expression for the relativistic time delay, and finally explain why Samuel's "theory" is conceptually incorrect and confuses the speed of gravity with the speed of light.

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Sergei M. Kopeikin. 2005-01-04. Comments on the paper by S. Samuel "On the speed of gravity and the Jupiter/Quasar measurement". https://doi.org/10.1142/s021827180600853x

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