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Quantum geometrodynamical description of the Universe in different reference frames

T. P. Shestakova
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Abstract

Several years ago the so-called quantum geometrodynamics in extended phase space was proposed. The main role in this version of quantum geometrodynamics is given to a wave function that carries information about geometry of the Universe as well as about a reference frame in which this geometry is studied. We consider the evolution of a physical object (the Universe) in ``physical'' subspace of extended configurational space, the latter including gauge and ghost degrees of freedom. A measure of the ``physical'' subspace depends on a chosen reference frame, in particular, a small variation of a gauge-fixing function results in changing the measure. Thus, a transition to another gauge condition (another reference frame) leads to non-unitary transformation of a physical part of the wave function. From the viewpoint of the evolution of the Universe in the ``physical'' subspace a transition to another reference frame is an irreversible process that may be important when spacetime manifold has a nontrivial topology.

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T. P. Shestakova. 2002-05-16. Quantum geometrodynamical description of the Universe in different reference frames. https://arxiv.org/abs/gr-qc/0205068

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