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arXiv · 1503.06785

Escher in the Sky

Renata Kallosh·Andrei Linde
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Abstract

The cosmological models called $\alpha$-attractors provide an excellent fit to the latest observational data. Their predictions $n_{s} = 1-2/N$ and $r = 12\alpha/N^{2}$ are very robust with respect to the modifications of the inflaton potential. An intriguing interpretation of $\alpha$-attractors is based on a geometric moduli space with a boundary: a Poincare disk model of a hyperbolic geometry with the radius $\sqrt{3\alpha}$, beautifully represented by the Escher's picture Circle Limit IV. In such models, the amplitude of the gravitational waves is proportional to the square of the radius of the Poincare disk.

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Renata Kallosh, Andrei Linde. 2015-03-23. Escher in the Sky. https://doi.org/10.1016/j.crhy.2015.07.004

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