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arXiv · 1905.01803

Probing cosmic anisotropy with GW/FRB as upgraded standard sirens

Rong-Gen Cai·Tong-Bo Liu·Shao-Jiang Wang·Wu-Tao Xu
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Abstract

Recently it was shown that cosmic anisotropy can be well tested using either standard siren measurement of luminosity distance $d_\mathrm{L}(z)$ from gravitational-wave (GW) observation or dispersion measure ($\mathrm{DM}(z)$) from fast radio burst (FRB). It was also observed that the combined measurement of $d_\mathrm{L}(z)\cdot\mathrm{DM}(z)$ from the GW/FRB association system as suggested in some of FRB models is more effective to constrain cosmological parameters than $d_\mathrm{L}(z)$ or $\mathrm{DM}(z)$ separately due to its independence from Hubble constant. In this paper, we will show both theoretically and with simulation that, this upgraded sirens from combined GW/FRB observations could test cosmic anisotropy with a double relative sensitivity compared to the usual standard siren from GW observation alone.

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Rong-Gen Cai, Tong-Bo Liu, Shao-Jiang Wang, Wu-Tao Xu. 2019-05-06. Probing cosmic anisotropy with GW/FRB as upgraded standard sirens. https://doi.org/10.1088/1475-7516%2F2019%2F09%2F016

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