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arXiv · 2005.01762

Stable, non-singular bouncing universe with only a scalar mode

K. Sravan Kumar·Shubham Maheshwari·Anupam Mazumdar·Jun Peng
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Abstract

In this paper, we study a class of higher derivative, non-local gravity which admits homogeneous and isotropic non-singular, bouncing universes in the absence of matter. At the linearized level, the theory propagates only a scalar degree of freedom, and no vector or tensor modes. The scalar can be made free from perturbative ghost instabilities, and has oscillatory and bounded evolution across the bounce.

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K. Sravan Kumar, Shubham Maheshwari, Anupam Mazumdar, Jun Peng. 2020-05-04. Stable, non-singular bouncing universe with only a scalar mode. https://doi.org/10.1103/physrevd.102.024080

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