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Is Minisuperspace Quantum Gravity Reliable?

O. Saremi
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Abstract

We study a minisuperspace quantum cosmology for a 2+1 dimensional de Sitter universe and find the wave function both exactly and in WKB approximation. Then we extend the model to a canonically quantized field theory for quantum gravity, i.e., a midisuperspace, and obtain the wave functional of the resulting field theory in the saddle point approximation. It is shown that these two approaches yield different results.

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O. Saremi. 2001-02-13. Is Minisuperspace Quantum Gravity Reliable?. https://arxiv.org/abs/gr-qc/0101108

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