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An Observational Test of Two-field Inflation

David Wands·Nicola Bartolo·Sabino Matarrese·Antonio Riotto
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Abstract

We study adiabatic and isocurvature perturbation spectra produced by a period of cosmological inflation driven by two scalar fields. We show that there exists a model-independent consistency condition for all two-field models of slow-roll inflation, despite allowing for model-dependent linear processing of curvature and isocurvature perturbations during and after inflation on super-horizon scales. The scale-dependence of all spectra are determined solely in terms of slow-roll parameters during inflation and the dimensionless cross-correlation between curvature and isocurvature perturbations. We present additional model-dependent consistency relations that may be derived in specific two-field models, such as the curvaton scenario.

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David Wands, Nicola Bartolo, Sabino Matarrese, Antonio Riotto. 2002-07-22. An Observational Test of Two-field Inflation. https://doi.org/10.1103/physrevd.66.043520

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