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Minimal Closed Set of Observables in the Theory of Cosmological Perturbations

M. Novello·J. M. Salim·M. C. Motta da Silva·S. E. Joras·R. Klippert
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Abstract

The theory of perturbation of Friedman-Robertson-Walker (FRW) cosmology is analysed exclusively in terms of observable quantities. Although this can be a very complete and general procedure we limit our presentation here to the case of irrotational perturbations for simplicity. We show that the electric part of Weyl conformal tensor {\bf $E$} and the shear {\bf $Σ$} constitute the two basic perturbed variables in terms of which all remaining observable quantities can be described. Einstein\rq s equations of General Relativity reduce to a closed set of dynamical system for {\bf $E$} and {\bf $Σ$}. The basis for a gauge-invariant Hamiltonian treatment of the Perturbation Theory in the FRW background is then set up.

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M. Novello, J. M. Salim, M. C. Motta da Silva, S. E. Joras, R. Klippert. 1994-03-11. Minimal Closed Set of Observables in the Theory of Cosmological Perturbations. https://doi.org/10.1103/physrevd.51.450

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