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arXiv · 1912.12600

A gigaparsec-scale local void and the Hubble tension

Qianhang Ding·Tomohiro Nakama·Yi Wang
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Abstract

We explore the possibility of using a gigaparsec-scale local void to reconcile the Hubble tension. Such a gigaparsec-scale void can be produced by multi-stream inflation where different parts of the observable universe follow different inflationary trajectories. The impact of such a void for cosmological observations is studied, especially those involving supernovae, Baryon Acoustic Oscillations (BAO) and the kinetic Sunyaev-Zel'dovich (kSZ) effect. As a benchmark model, a 1.7Gpc scale with boundary width 0.7Gpc and density contrast -0.14 may ease the Hubble tension.

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Qianhang Ding, Tomohiro Nakama, Yi Wang. 2019-12-29. A gigaparsec-scale local void and the Hubble tension. https://arxiv.org/abs/1912.12600

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