Predictions in multifield models of inflation

Abstract

This paper presents a method for obtaining an analytic expression for the density function of observables in multifield models of inflation with sum-separable potentials. The most striking result is that the density function in general possesses a sharp peak and the location of this peak is only mildly sensitive to the distribution of initial conditions. A simple argument is given for why this result holds for a more general class of models than just those with sum-separable potentials and why for such models, it is possible to obtain robust predictions for observable quantities. As an example, the joint density function of the spectral index and running in double quadratic inflation is computed. For scales leaving the horizon 55 e-folds before the end of inflation, the density function peaks at n_{s}=0.967 and α=0.0006 for the spectral index and running respectively.

16 pages, 6 figures, updated to match version published in JCAP. New plot added

References in corpus (13)

• Non-Gaussianities in two-field inflation
• Inflation after WMAP3: Confronting the Slow-Roll and Exact Power Spectra with CMB Data
• Curvature and isocurvature perturbations in two-field inflation
• Primordial Non-Gaussianity in Multi-Scalar Slow-Roll Inflation
• Non-gaussianity and cosmic uncertainty in curvaton-type models
• Nflation: non-gaussianity in the horizon-crossing approximation
• Inflationary perturbation theory is geometrical optics in phase space
• Moment transport equations for the primordial curvature perturbation
• Exploring a string-like landscape
• Numerical calculation of second order perturbations
• Preference for a Vanishingly Small Cosmological Constant in Supersymmetric Vacua in a Type IIB String Theory Model
• Initial conditions and sampling for multifield inflation
• Testing Two-Field Inflation

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