Large N cosmology

Robert Brandenberger, Pei Ming Ho, Hsien Chung Kao

Research output: Contribution to journalReview article

14 Citations (Scopus)

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.

Original languageEnglish
Pages (from-to)159-177
Number of pages19
JournalJournal of Cosmology and Astroparticle Physics
Issue number11
DOIs
Publication statusPublished - 2004 Nov 1

Fingerprint

cosmology
invariance
entropy
scalars
formulations
perturbation
symmetry

Keywords

  • Cosmological perturbation theory
  • Inflation

ASJC Scopus subject areas

  • Astronomy and Astrophysics

Cite this

Large N cosmology. / Brandenberger, Robert; Ho, Pei Ming; Kao, Hsien Chung.

In: Journal of Cosmology and Astroparticle Physics, No. 11, 01.11.2004, p. 159-177.

Research output: Contribution to journalReview article

Brandenberger, Robert ; Ho, Pei Ming ; Kao, Hsien Chung. / Large N cosmology. In: Journal of Cosmology and Astroparticle Physics. 2004 ; No. 11. pp. 159-177.
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