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arXiv · 1812.10433

Probing the time variation of the effective Newton's constant with optimal redshift weights

Jian Li·Gong-Bo Zhao
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Abstract

We propose a new method for probing the time variation of the effective Newton's constant $G_{\rm eff}$, based on the optimal redshift weighting scheme, and demonstrate the efficacy using the DESI galaxy spectroscopic survey. We find that with the optimal redshift weights, the evolution of $G_{\rm eff}(z)$ can be significantly better measured: the uncertainty of $G_{\rm eff}(z)$ can be reduced by a factor of $2.2\sim12.8$ using the DESI BGS sample at $z \lesssim0.45$, and by a factor of $1.3\sim4.4$ using the DESI ELG sample covering $0.65\lesssim z\lesssim1.65$.

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Jian Li, Gong-Bo Zhao. 2019-05-16. Probing the time variation of the effective Newton's constant with optimal redshift weights. https://doi.org/10.3847/1538-4357%2Fab16eb

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