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Constraining Brans-Dicke Gravity with Millisecond Pulsars in Ultracompact Binaries

Dimitrios Psaltis
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Abstract

The five accreting, millisecond X-ray pulsars in ultracompact binaries that were recently discovered with the Rossi X-ray Timing Explorer provide excellent candidates for constraining the deviations from general relativity described by the Brans-Dicke parameter omega_BD. I calculate the expected rate of change of the orbital periods of these binaries and discuss the prospects of constraining omega_BD to values that are an order of magnitude larger than current constraints. Finally, I show how measurements of the orbital period derivative in ultracompact binaries can be used to place lower bounds on their orbital inclination.

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Dimitrios Psaltis. 2005-01-12. Constraining Brans-Dicke Gravity with Millisecond Pulsars in Ultracompact Binaries. https://arxiv.org/abs/astro-ph/0501234

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