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Spacetime Singularities in (2+1)-Dimensional Quantum Gravity

Eric A. Minassian
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Abstract

The effects of spacetime quantization on black hole and big bang/big crunch singularities can be studied using new tools from (2+1)-dimensional quantum gravity. I investigate effects of spacetime quantization on singularities of the (2+1)-dimensional BTZ black hole and the (2+1)-dimensional torus universe. Hosoya has considered the BTZ black hole, and using a ``quantum generalized affine parameter'' (QGAP), has shown that, for some specific paths, quantum effects ``smear'' the singularity. Using generic gaussian wave functions, I show that both BTZ black hole and the torus universe contain families of paths that still reach the singularities with a finite QGAP, suggesting that singularities persist in quantum gravity. More realistic calculations, using modular invariant wave functions of Carlip and Nelson for the torus universe, further support this conclusion.

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Eric A. Minassian. 2002-03-08. Spacetime Singularities in (2+1)-Dimensional Quantum Gravity. https://doi.org/10.1088/0264-9381%2F19%2F23%2F301

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