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Gravitons in One-Loop Quantum Cosmology: Correspondence Between Covariant and Non-Covariant Formalisms

Giampiero Esposito·Alexander Yu. Kamenshchik·Igor V. Mishakov·Giuseppe Pollifrone
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Abstract

The discrepancy between the results of covariant and non-covariant one-loop calculations for higher-spin fields in quantum cosmology is analyzed. A detailed mode-by-mode study of perturbative quantum gravity about a flat Euclidean background bounded by two concentric 3-spheres, including non-physical degrees of freedom and ghost modes, leads to one-loop amplitudes in agreement with the covariant Schwinger-DeWitt method. This calculation provides the generalization of a previous analysis of fermionic fields and electromagnetic fields at one-loop about flat Euclidean backgrounds admitting a well-defined 3+1 decomposition.

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Giampiero Esposito, Alexander Yu. Kamenshchik, Igor V. Mishakov, Giuseppe Pollifrone. 1995-06-28. Gravitons in One-Loop Quantum Cosmology: Correspondence Between Covariant and Non-Covariant Formalisms. https://doi.org/10.1103/physrevd.50.6329

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