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Singularity avoidance by collapsing shells in quantum gravity

Petr Hajicek·Claus Kiefer
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Abstract

We discuss a model describing exactly a thin spherically symmetric shell of matter with zero rest mass. We derive the reduced formulation of this system in which the variables are embeddings, their conjugate momenta, and Dirac observables. A non-perturbative quantum theory of this model is then constructed, leading to a unitary dynamics. As a consequence of unitarity, the classical singularity is fully avoided in the quantum theory.

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Petr Hajicek, Claus Kiefer. 2001-07-31. Singularity avoidance by collapsing shells in quantum gravity. https://doi.org/10.1142/s0218271801001578

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