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arXiv · 2012.12462

Measuring the viscosity of dark matter with strongly lensed gravitational waves

Shuo Cao·Jingzhao Qi·Marek Biesiada·Tonghua Liu·Jin Li·Zong-Hong Zhu
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Abstract

Based on the strongly lensed gravitational waves (GWs) from compact binary coalescence, we propose a new strategy to examine the fluid shear viscosity of dark matter (DM) in the gravitational wave domain, i.e., whether a GW experiences the damping effect when it propagates in DM fluid with nonzero shear viscosity. By assuming that the dark matter self-scatterings are efficient enough for the hydrodynamic description to be valid, our results demonstrate that future ground-based Einstein Telescope (ET) and satellite GW observatory (Big Bang Observer; BBO) may succeed in detecting any dark matter self-interactions at the scales of galaxies and clusters.

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Shuo Cao, Jingzhao Qi, Marek Biesiada, Tonghua Liu, Jin Li, Zong-Hong Zhu. 2020-12-23. Measuring the viscosity of dark matter with strongly lensed gravitational waves. https://doi.org/10.1093/mnrasl%2Fslaa205

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