arXiv subjects

S. P. Labazova

Publications and source records attributed to S. P. Labazova.

2 recordsLinked to original sources

arXiv2021

On Shapiro time delay in massive scalar-tensor theories

The problem of determining the post-Newtonian parameter $γ$ in massive scalar-tensor theories is considered. We demonstrate equivalent correspondence between the post-Newtonian parameter $γ$ 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.

gr-qc↗

arXiv2019

Post-Newtonian limit of hybrid metric-Palatini f(R)-gravity

Using the latest most accurate values of post-Newtonian parameters $γ$ and $β$ obtained by MESSENGER we impose restrictions on the recently proposed hybrid f(R)-gravity model in its scalar-tensor representation. We show that the presence of a light scalar field in this theory does not contradict the experimental data based not only on the $ γ$ parameter (as was shown earlier), but also on all other PPN parameters. The application of parameterized post-Newtonian formalism to gravitational theories with massive fields is also discussed.

gr-qc↗