Particle physics models of inflation and the cosmological density perturbation
Abstract
This is a review of particletheory models of inflation, and of their predictions for the primordial density perturbation that is thought to be the origin of structure in the Universe. It contains minireviews of the relevant observational cosmology, of elementary field theory and of supersymmetry, that may be of interest in their own right. The spectral index /n(k), specifying the scale dependence of the spectrum of the curvature perturbation, will be a powerful discriminator between models, when it is measured by Planck with accuracy /Δn~0.01. The usual formula for /n is derived, as well as its less familiar extension to the case of a multicomponent inflaton; in both cases the key ingredient is the separate evolution of causally disconnected regions of the Universe. Primordial gravitational waves will be an even more powerful discriminator if they are observed, since most models of inflation predict that they are completely negligible. We treat in detail the new wave of models, which are firmly rooted in modern particle theory and have supersymmetry as a crucial ingredient. The review is addressed to both astrophysicists and particle physicists, and each section is fairly homogeneous regarding the assumed background knowledge.
 Publication:

Physics Reports
 Pub Date:
 June 1999
 DOI:
 10.1016/S03701573(98)001288
 arXiv:
 arXiv:hepph/9807278
 Bibcode:
 1999PhR...314....1L
 Keywords:

 High Energy Physics  Phenomenology;
 Astrophysics;
 General Relativity and Quantum Cosmology;
 High Energy Physics  Theory
 EPrint:
 156 pages, after final proof corrections and additions