Dynamic field theory and equations of motion in cosmology
We discuss a fieldtheoretical approach based on generalrelativistic variational principle to derive the covariant field equations and hydrodynamic equations of motion of baryonic matter governed by cosmological perturbations of dark matter and dark energy. The action depends on the gravitational and matter Lagrangian. The gravitational Lagrangian depends on the metric tensor and its first and second derivatives. The matter Lagrangian includes dark matter, dark energy and the ordinary baryonic matter which plays the role of a bare perturbation. The total Lagrangian is expanded in an asymptotic Taylor series around the background cosmological manifold defined as a solution of Einstein’s equations in the form of the Friedmann–Lemaître–Robertson–Walker (FLRW) metric tensor. The small parameter of the decomposition is the magnitude of the metric tensor perturbation. Each term of the series expansion is gaugeinvariant and all of them together form a basis for the successive postFriedmannian approximations around the background metric. The approximation scheme is covariant and the asymptotic nature of the Lagrangian decomposition does not require the postFriedmannian perturbations to be small though computationally it works the most effectively when the perturbed metric is close enough to the background FLRW metric. The temporal evolution of the background metric is governed by darkmore »
 Authors:

^{[1]};
^{[2]}
 Department of Physics and Astronomy, University of Missouri, 322 Physics Bldg., Columbia, MO 65211 (United States)
 Sternberg Astronomical Institute, Lomonosov Moscow State University, Universitetskij Prospect 13, Moscow 119992 (Russian Federation)
 Publication Date:
 OSTI Identifier:
 22403444
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Annals of Physics (New York); Journal Volume: 350; Other Information: Copyright (c) 2014 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved.; Country of input: International Atomic Energy Agency (IAEA)
 Country of Publication:
 United States
 Language:
 English
 Subject:
 71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; ASTROPHYSICS; ASYMPTOTIC SOLUTIONS; BARYONS; DISTURBANCES; EINSTEIN FIELD EQUATIONS; EQUATIONS OF MOTION; FIELD THEORIES; GALAXIES; GAUGE INVARIANCE; GRAVITATION; LAGRANGIAN FUNCTION; NONLUMINOUS MATTER; RELATIVISTIC RANGE; SERIES EXPANSION; STARS; TENSORS; VARIATIONAL METHODS