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arXiv · 1110.5480

Coherent State Functional Integrals in Quantum Cosmology

Li Qin·Yongge Ma
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Abstract

Coherent state functional integrals for the minisuperspace models of quantum cosmology are studied. By the well-established canonical theories, the transition amplitudes in the path-integral representations of Wheeler-DeWitt quantum cosmology and loop quantum cosmology can be formulated through group averaging. The effective action and Hamiltonian with higher-order quantum corrections are thus obtained in both models. It turns out that for a non-symmetric Hamiltonian constraint operator, the Moyal (star)-product emerges naturally in the effective Hamiltonian. This reveals the intrinsic relation among coherent state functional integral, effective theory and star-product. Moreover, both the resulted effective theories imply a possible quantum cosmological effect in large scale limit.

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Li Qin, Yongge Ma. 2012-03-28. Coherent State Functional Integrals in Quantum Cosmology. https://doi.org/10.1103/physrevd.85.063515

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