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arXiv · 1706.09620

Axial gravitational waves in FLRW cosmology and memory effects

Wojciech Kulczycki·Edward Malec
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Abstract

We show initial data for gravitational axial waves, that are twice differentiable but which are not $C^{2}$. They generate wave pulses that interact with matter in the radiation cosmological era. This forces the radiation matter to rotate. This rotation is permanent - it persists after the passage of the gravitational pulse. The observed inhomogeneities of the cosmic microwave background radiation put a bound onto discontinuities of superhorizon metric perturbations. We explicitly show that a class of smooth initial metrics that are at least $C^{2}$ gives rise to gravitational wave pulses that do not interact with the background during the radiation epoch.

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Wojciech Kulczycki, Edward Malec. 2017-06-29. Axial gravitational waves in FLRW cosmology and memory effects. https://doi.org/10.1103/physrevd.96.063523

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