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arXiv · 1901.01905

Schwinger-Keldysh mechanism in extended quasi single field inflation

Haidar Sheikhahmadi
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Abstract

We study an extension of quasi-single field model of inflation containing multiple semi-heavy isocurvaton fields using the Schwinger-Keldysh mechanism. We calculate the amplitudes and the shapes of the bispectrum and the trispectrum. We show that the diagrammatic approach associated with the Schwinger-Keldysh mechanism simplifies the analysis considerably compared to standard in-in formalism. This method is helpful to study the spectroscopy of masses and couplings of light and semi-heavy fields during inflation.

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Haidar Sheikhahmadi. 2019-01-07. Schwinger-Keldysh mechanism in extended quasi single field inflation. https://doi.org/10.1140/epjc%2Fs10052-019-6969-z

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