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Relation between the guessed and the derived super-Hamiltonians for spherically symmetric shells

P. Hajicek
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Abstract

The Hamiltonian dynamics of spherically symmetric massive thin shells in the general relativity is studied. Two different constraint dynamical systems representing this dynamics have been described recently; the relation of these two systems is investigated. The symmetry groups of both systems are found. New variables are used, which among other things simplify the complicated system a great deal. The systems are reduced to presymplectic manifolds Gamma_1 and Gamma_2, lest non-physical aspects like gauge fixings or embeddings in extended phase spaces complicate the line of reasoning. The following facts are shown. Gamma_1 is three- and Gamma_2 is five-dimensional; the description of the shell dynamics by Gamma_1 is incomplete so that some measurable properties of the shell cannot be predicted. Gamma_1 is locally equivalent to a subsystem of Gamma_2 and the corresponding local morphisms are not unique, due to the large symmetry group of Gamma_2. Some consequences for the recent extensions of the quantum shell dynamics through the singularity are discussed.

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P. Hajicek. 1998-05-11. Relation between the guessed and the derived super-Hamiltonians for spherically symmetric shells. https://doi.org/10.1103/physrevd.58.084005

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