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arXiv · 2204.04110

Rotating cosmologies: classical and quantum

Alberto Nicolis·Federico Piazza·Kenza Zeghari
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Abstract

We revisit spatially flat, anisotropic cosmologies within the framework of mini-superspace. Putting special emphasis on the symmetries of the mini-superspace action and on the associated conservation laws, we unveil a new class of rotating cosmologies driven by solid matter. Their rotating is physical, in that it is characterized in an invariant way in terms of a conserved angular momentum. Along the way, we confirm the results of Bartolo et al. regarding the slow decay of anisotropies for solid inflation. We then use our minisuperspace approach as a laboratory to address certain puzzles of quantum cosmology-among these, how to characterize the spacetime symmetries of a quantum state at the level of the wavefunction of the universe. For the case of a solid driven cosmology, this question seems better defined than in more standard cases. Other questions remain unanswered, though; in particular, the general question of how to operate a minisuperspace-like truncation of degrees of freedom that is consistent at the quantum level.

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Alberto Nicolis, Federico Piazza, Kenza Zeghari. 2022-04-08. Rotating cosmologies: classical and quantum. https://doi.org/10.1088/1475-7516%2F2022%2F10%2F059

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