Large N Cosmology

Abstract

We motivate inflationary scenarios with many scalar fields, and give a complete formulation of adiabatic and entropy perturbations. We find that if the potential is very flat, or if the theory has a SO(N) symmetry, the calculation of the fluctuation spectrum can be carried out in terms of merely two variables without any further assumption. We do not have to assume slow roll or SO(N) invariance for the background fields. We give some examples to show that, even if the slow roll assumption holds, the spectrum of fluctuations can be quite different from the case when there is a single inflaton.

LaTex file, 22 pages, references added

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Cited by in corpus (22)

• N-flation
• Particle physics models of inflation and curvaton scenarios
• Gauge invariant MSSM inflaton
• On the Possibility of Large Axion Moduli Spaces
• Inflation with multiple sound speeds: a model of multiple DBI type actions and non-Gaussianities
• A-term inflation and the smallness of the neutrino masses
• M-flation: Inflation From Matrix Valued Scalar Fields
• Inflation in large N limit of supersymmetric gauge theories
• Inflection point inflation within supersymmetry
• N-flation from multiple DBI type actions
• Reheating in supersymmetric high scale inflation
• On Perturbation Spectra of N-flation
• Current Acceleration from Dilaton and Stringy Cold Dark Matter
• Inflation Assisted by Heterotic Axions
• The Strong Multifield Slowroll Condition and Spiral Inflation
• Enhanced Inflation in the Dirac-Born-Infeld framework
• On Number of Nflation Fields
• The Measure for the Multiverse and the Probability for Inflation
• New developments on embedding inflation in gauge theory and particle physics
• Spectrum of Curvature Perturbation of Multi-field Inflation with Small-Field Potential
• Phase Diagram for Nflation
• Inflation from multiple flat directions