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The spectrum of density perturbations in an expanding universeThe basic dynamic equations that govern the evolution of perturbations in a Friedmann-Lemaitre universe are derived. General solutions describing the evolution of adiabatic perturbations in the density of matter are obtained, and the choice of the appropriate initial conditions is examined. The various perturbation modes are compared, and the effects of decoupling on the perturbation spectrum are studied. The scheme used to follow the evolution of density perturbations through decoupling is based on an extension of the Eddington approximation to the radiative transfer equation, and is strictly valid in both optically thick and thin limits.
Document ID
19750037769
Document Type
Conference Proceedings
Authors
Silk, J.
Date Acquired
August 8, 2013
Publication Date
January 1, 1974
Subject Category
ASTROPHYSICS
Meeting Information
Confrontation of cosmological theories with observational data; Symposium(Krakow)
Funding Number(s)
CONTRACT_GRANT: NGR-05-003-453
Distribution Limits
Public
Copyright
Other