Stringy signals from large-angle correlations in the cosmic microwave background?

Miguel-Angel Sanchis-Lozano

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arXiv · 2205.13257

Stringy signals from large-angle correlations in the cosmic microwave background?

Miguel-Angel Sanchis-Lozano

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Abstract

We interpret the lack of large-angle temperature correlations and the apparent even-odd parity imbalance, observed in the cosmic microwave background by COBE, WMAP and Planck satellite missions, as a possible stringy signal ultimately stemming from a composite inflaton field (e.g. a fermionic condensate). Based on causality arguments and a Fourier analysis of the angular two-point correlation function, two infrared cutoffs $k_{\rm min}^{\rm even,odd}$ are introduced in the CMB power spectrum associated, respectively, with periodic and antiperiodic boundary conditions of the fermionic constituents (echoing the Neveu-Schwarz-Ramond model in superstring theory), without resorting to any particular model.

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Miguel-Angel Sanchis-Lozano. 2022-05-26. Stringy signals from large-angle correlations in the cosmic microwave background?. https://arxiv.org/abs/2205.13257

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