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Neutron Stars in a Varying Speed of Light Theory

A. W. Whinnett
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Abstract

We study neutron stars in a varying speed of light (VSL) theory of gravity in which the local speed of light depends upon the value of a scalar field $ϕ$. We find that the masses and radii of the stars are strongly dependent on the strength of the coupling between $ϕ$ and the matter field and that for certain choices of coupling parameters, the maximum neutron star mass can be arbitrarily small. We also discuss the phenomenon of cosmological evolution of VSL stars (analogous to the gravitational evolution in scalar-tensor theories) and we derive a relation showing how the fractional change in the energy of a star is related to the change in the cosmological value of the scalar field.

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A. W. Whinnett. 2003-05-21. Neutron Stars in a Varying Speed of Light Theory. https://doi.org/10.1103/physrevd.68.024009

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