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arXiv · 1404.5284

Fluctuation energies in quantum cosmology

Martin Bojowald
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Abstract

Quantum fluctuations or other moments of a state contribute to energy expectation values and can imply interesting physical effects. In quantum cosmology, they turn out to be important for a discussion of density bounds and instabilities of initial-value problems in the presence of signature change in loop-quantized models. This article provides an effective description of these issues, accompanied by a comparison with existing numerical results and an extension to squeezed states. The comparison confirms that canonical effective methods are well-suited for computations of properties of physical states. As a side product, an example is found for a simple state in which quantum fluctuations can cancel holonomy modifications of loop quantum cosmology.

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Martin Bojowald. 2014-04-21. Fluctuation energies in quantum cosmology. https://doi.org/10.1103/physrevd.89.124031

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