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arXiv · 1803.01961

Bouncing Cosmology made simple

Anna Ijjas·Paul J. Steinhardt
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Abstract

We introduce the "wedge diagram," an intuitive way to illustrate how cosmological models with a classical (non-singular) bounce generically resolve fundamental problems in cosmology. These include the well-known horizon, flatness, and inhomogeneity problems; the small tensor-to-scalar ratio observed in the cosmic microwave background; the low entropy at the beginning of a hot, expanding phase; and the avoidance of quantum runaway. The same diagrammatic approach can be used to compare with other cosmological scenarios.

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Anna Ijjas, Paul J. Steinhardt. 2018-03-06. Bouncing Cosmology made simple. https://doi.org/10.1088/1361-6382%2Faac482

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