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arXiv · 0805.4099

Signature change from Schutz's canonical quantum cosmology and its classical analogue

P. Pedram·S. Jalalzadeh
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Abstract

We study the signature change in a perfect fluid Friedmann-Robertson-Walker quantum cosmological model. In this work the Schutz's variational formalism is applied to recover the notion of time. This gives rise to a Schrodinger-Wheeler-DeWitt equation with arbitrary ordering for the scale factor. We use the eigenfunctions in order to construct wave packets and evaluate the time-dependent expectation value of the scale factor which coincides with the ontological interpretation. We show that these solutions exhibit signature transitions from a finite Euclidean to a Lorentzian domain. Moreover, such models are equivalent to a classical system where, besides the perfect fluid, a repulsive fluid is present.

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P. Pedram, S. Jalalzadeh. 2008-05-27. Signature change from Schutz's canonical quantum cosmology and its classical analogue. https://doi.org/10.1103/physrevd.77.123529

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