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arXiv · 1802.05532

Strongly gravitational lensed SNe Ia as multi-messengers: Direct test of the Friedmann-Lema\^ıtre-Robertson-Walker metric

Jing-Zhao Qi·Shou Cao·Marek Biesiada·Xiaogang Zheng·Xuheng Ding·Zong-Hong Zhu
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Abstract

We present a new idea of testing the validity of the Friedman-Lema\^ıtre-Robertson-Walker metric, through the multiple measurements of galactic-scale strong gravitational lensing systems with type Ia supernovae in the role of sources. Each individual lensing system will provide a model-independent measurement of the spatial curvature parameter referring only to geometrical optics independently of the matter content of the universe. This will create a valuable opportunity to test the FLRW metric directly. Our results show that with hundreds of strongly lensed SNe Ia observed by LSST, one would produce robust constraints on the spatial curvature with accuracy $ΔΩ_k=0.04$ comparable to the Planck 2015 results.

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Jing-Zhao Qi, Shou Cao, Marek Biesiada, Xiaogang Zheng, Xuheng Ding, Zong-Hong Zhu. 2019-06-24. Strongly gravitational lensed SNe Ia as multi-messengers: Direct test of the Friedmann-Lema\^ıtre-Robertson-Walker metric. https://doi.org/10.1103/physrevd.100.023530

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