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arXiv · 1509.02942

Platonic solids back in the sky: Icosahedral inflation

Jonghee Kang·Alberto Nicolis
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Abstract

We generalize the model of solid inflation to an anisotropic cosmic solid. Barring fine tunings, the observed isotropy of the cosmological background and of the scalar two-point function isolate the icosahedral group as the only possible symmetry group of such a solid. In such a case, higher-point correlation functions---starting with the three-point one---are naturally maximally anisotropic, which makes the standard detection strategies highly inefficient and calls for a dedicated analysis of CMB data. The tensor two-point function can also be highly anisotropic, but only in the presence of sizable higher-derivative couplings.

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Jonghee Kang, Alberto Nicolis. 2015-09-09. Platonic solids back in the sky: Icosahedral inflation. https://doi.org/10.1088/1475-7516%2F2016%2F03%2F050

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