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Factor ordering in standard quantum cosmology

Roman Steigl·Franz Hinterleitner
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Abstract

The Wheeler-DeWitt equation of Friedmann models with a massless quantum field is formulated with arbitrary factor ordering of the Hamiltonian constraint operator. A scalar product of wave functions is constructed, giving rise to a probability interpretation and making comparison with the classical solution possible. In general the bahaviour of the wave function of the model depends on a critical energy of the matter field, which, in turn, depends on the chosen factor ordering. By certain choices of the ordering the critical energy can be pushed down to zero.

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Roman Steigl, Franz Hinterleitner. 2005-11-29. Factor ordering in standard quantum cosmology. https://doi.org/10.1088/0264-9381%2F23%2F11%2F013

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