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On the Physical Hilbert Space of Loop Quantum Cosmology

Karim Noui·Alejandro Perez·Kevin Vandersloot
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Abstract

In this paper we present a model of Riemannian loop quantum cosmology with a self-adjoint quantum scalar constraint. The physical Hilbert space is constructed using refined algebraic quantization. When matter is included in the form of a cosmological constant, the model is exactly solvable and we show explicitly that the physical Hilbert space is separable consisting of a single physical state. We extend the model to the Lorentzian sector and discuss important implications for standard loop quantum cosmology.

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Karim Noui, Alejandro Perez, Kevin Vandersloot. 2004-11-09. On the Physical Hilbert Space of Loop Quantum Cosmology. https://doi.org/10.1103/physrevd.71.044025

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