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Hamiltonian reduction of Bianchi Cosmologies

J. Schirmer
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Abstract

It was noted recently that the ADM-diffeomorphism-constraint does not generate all observed symmetries for several Bianchi-models. We will suggest not to use the ADM-constraint restricted to homogeneous variables, but some equivalent which is derived from a restricted action principle. This will generate all homogeneity preserving diffeomorphisms, which will be shown to be automorphism generating vector fields, in class A and class B models. Following Dirac's constraint formalism one will naturally be restricted to the unimodular part of the automorphism group.

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J. Schirmer. 1994-08-04. Hamiltonian reduction of Bianchi Cosmologies. https://doi.org/10.1088/0264-9381%2F12%2F4%2F017

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