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arXiv · 2111.13900

On Shapiro time delay in massive scalar-tensor theories

P. I. Dyadina·S. P. Labazova
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Abstract

The problem of determining the post-Newtonian parameter $\gamma$ in massive scalar-tensor theories is considered. We demonstrate equivalent correspondence between the post-Newtonian parameter $\gamma$ and the parameter appearing in the equation of null geodysic in massive scalar-tensor theories. We show that massive scalar-tensor theories can be distinguished from general relativity based on the predictions of Shapiro time delay. All calculations are presented using hybrid metric-Palatini f(R)-gravity as an example. The expression for Shapiro time delay in hybrid f(R)-gravity is obtained for the first time.

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P. I. Dyadina, S. P. Labazova. 2021-11-27. On Shapiro time delay in massive scalar-tensor theories. https://doi.org/10.1088/1475-7516%2F2022%2F01%2F029

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