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arXiv · 1412.1492

Superselection rule for the cosmological constant in three-dimensional spacetime

Claudio Bunster·Alfredo Perez
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Abstract

Efforts to understand the origin of the cosmological constant Λ and its observed value have led to consider it as a dynamical field rather than as a universal constant. Then the possibility arises that the universe, or regions of it, might be in a superposition of quantum states with different values of Λ, so that its actual value would not be definite. There appears to be no argument to rule out this possibility for a generic spacetime dimension D. However, as proved herein, for D=3 there exists a superselection rule that forbids such superpositions. The proof is based on the asymptotic symmetry algebra.

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Claudio Bunster, Alfredo Perez. 2014-12-03. Superselection rule for the cosmological constant in three-dimensional spacetime. https://doi.org/10.1103/physrevd.91.024029

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