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Geometrodynamics in a spherically symmetric, static crossflow of null dust

Zsolt Horváth·Zoltán Kovács·László Á. Gergely
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Abstract

The spherically symmetric, static spacetime generated by a crossflow of non-interacting radiation streams, treated in the geometrical optics limit (null dust) is equivalent to an anisotropic fluid forming a radiation atmosphere of a star. This reference fluid provides a preferred / internal time, which is employed as a canonical coordinate. Among the advantages we encounter a new Hamiltonian constraint, which becomes linear in the momentum conjugate to the internal time (therefore yielding a functional Schrödinger equation after quantization), and a strongly commuting algebra of the new constraints.

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Zsolt Horváth, Zoltán Kovács, László Á. Gergely. 2006-10-12. Geometrodynamics in a spherically symmetric, static crossflow of null dust. https://doi.org/10.1103/physrevd.74.084034

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