arXiv subjects

Shawn D. Belknap-Keet

Publications and source records attributed to Shawn D. Belknap-Keet.

3 recordsLinked to original sources

arXiv2018

Symmetry of Brans-Dicke gravity as a novel solution-generating technique

A symmetry of Brans-Dicke gravity in (electro-)vacuo or in the presence of conformally invariant matter is presented and used as a solution-generating technique starting from a known solution as a seed. This novel technique is applied to generate, as examples, new spatially homogeneous and isotropic cosmologies, a 3-parameter family of spherical time-dependent spacetimes conformal to a Campanelli-Lousto geometry, and a family of cylindrically symmetric geometries.

gr-qc↗

arXiv2017

New inhomogeneous universes in scalar-tensor and f(R) gravity

A new family of spherically symmetric inhomogeneous solutions of Brans-Dicke gravity is generated using the Fonarev solution of general relativity as a seed and a map from the Einstein to the Jordan conformal frame. The Brans-Dicke scalar field self-interacts with a power-law or inverse power-law potential in the Jordan frame. This 4-parameter family of geometries, which is dynamical and asymptotically Friedmann-Lemaitre-Robertson-Walker, contains as special cases two previously known classes of solutions and solves also the field equations of $f(R)=R^n$ gravity

gr-qc↗

arXiv2016

Paczynski-Wiita-like potential for any static spherical black hole in metric theories of gravity

The pseudo-Newtonian potential of Paczynski and Wiita for particles orbiting a Schwarzschild black hole is generalized to arbitrary static and spherically symmetric spacetimes, including black hole solutions of alternative theories of gravity. In addition to being more general, our prescription differs substantially from a previous one in the literature, showing that even the association of a pseudo-Newtonian potential with a simple black hole metric is not unique.

gr-qc↗