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arXiv · 1904.04041

A model independent constraint on the temporal evolution of the speed of light

Dandan Wang·Hanyu Zhang·Jinglan Zheng·Yuting Wang·Gong-Bo Zhao
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Abstract

We present a new, model-independent method to reconstruct the temporal evolution of the speed of light $c(z)$ using astronomical observations. After validating our pipeline using mock datasets, we apply our method to the latest BAO and supernovae observations, and reconstruct $c(z)$ in the redshift range of $z\in[0,1.5]$. We find no evidence of a varying speed of light, although we see some interesting features of $\Delta c(z)$, the fractional difference between $c(z)$ and $c_0$ (the speed of light in SI), \eg, $\Delta c(z)<0$ and $\Delta c(z)>0$ at $0.2\lesssim z\lesssim0.5$ and $0.8\lesssim z\lesssim1.3$, respectively, although the significance of these features is currently far below statistical importance.

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Dandan Wang, Hanyu Zhang, Jinglan Zheng, Yuting Wang, Gong-Bo Zhao. 2019-04-08. A model independent constraint on the temporal evolution of the speed of light. https://doi.org/10.1088/1674-4527/19/10/152

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