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Geodesic deviation in pp-wave spacetimes of quadratic curvature gravity

Edgard C. de Rey Neto
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Abstract

We write the equation of geodesic deviations in the spacetime of $pp$-waves in terms of the Newman-Penrose scalars and apply it to study gravitational waves in quadratic curvature gravity. We show that quadratic curvature gravity $pp$-waves can have a transverse helicity-0 polarization mode and two transverse helicity-2 general relativity-like wave polarizations. A concrete example is given in which we analyze the wave polarizations of an exact impulsive gravitational wave solution to quadratic curvature gravity.

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Edgard C. de Rey Neto. 2003-09-26. Geodesic deviation in pp-wave spacetimes of quadratic curvature gravity. https://doi.org/10.1103/physrevd.68.124013

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