Spacetime Singularities in (2+1)-Dimensional Quantum Gravity
نویسنده
چکیده
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. ∗email: [email protected]
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