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arXiv · 0811.2176

Non-Gaussian Signatures from the Postinflationary Early Universe

Alessandra Silvestri·Mark Trodden
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Abstract

We consider contributions to non-Gaussianity of the Cosmic Microwave Background (CMB) from remnants of post-inflationary phase transitions in the very early universe. Such signatures can optimistically be used to discover evidence of new particle physics through cosmological observations. More conservatively they provide a potential obstacle to extracting information about the non-Gaussian nature of primordial density fluctuations from any detection in the CMB. We demonstrate this explicitly by computing the bispectrum from global textures, which may be generated from a wide class of particle physics models.

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Alessandra Silvestri, Mark Trodden. 2009-12-06. Non-Gaussian Signatures from the Postinflationary Early Universe. https://doi.org/10.1103/physrevlett.103.251301

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