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arXiv · 1801.08001

Curvature from strong gravitational lensing: a spatially closed Universe or systematics?

Zhengxiang Li·Xuheng Ding·Guo-Jian Wang·Kai Liao·Zong-Hong Zhu
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Abstract

Model-independent constraints on the spatial curvature are not only closely related to important problems such as the evolution of the Universe and properties of dark energy, but also provide a test of the validity of the fundamental Copernican principle. In this paper, with the distance sum rule in the Friedmann-Lema\^{i}tre-Robertson-Walker metric, we achieve model-independent measurements of the spatial curvature from the latest type Ia supernovae and strong gravitational lensing (SGL) observations. We find that a spatially closed Universe is preferred. Moreover, by considering different kinds of velocity dispersion and subsample, we study possible factors which might affect model-independent estimations for the spatial curvature from SGL observations. It is suggested that the combination of observational data from different surveys might cause a systematic bias and the tension between the spatially flat Universe and SGL observations is alleviated when the subsample only from the Sloan Lens ACS Survey is used or a more complex treatment for the density profile of lenses is considered.

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Zhengxiang Li, Xuheng Ding, Guo-Jian Wang, Kai Liao, Zong-Hong Zhu. 2018-01-24. Curvature from strong gravitational lensing: a spatially closed Universe or systematics?. https://doi.org/10.3847/1538-4357%2Faaa76f

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