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arXiv · hep-th/0503146

A Quantum Gravitational Relaxation of The Cosmological Constant

Stephon Alexander
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Abstract

Similar to QCD, general relativity has a $Θ$ sector due to large diffeomorphisms. We make explicit, for the first time, that the gravitational CP violating $Θ$ parameter is non-perturbatively related to the cosmological constant. A gravitational pseudoscalar coupling to massive fermions gives rise to general relativity from a topological $B\wedge F$ theory through a chiral symmetry breaking mechanism. We show that a gravitational Peccei-Quinn like mechanism can dynamically relax the cosmological constant.

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Stephon Alexander. 2005-03-18. A Quantum Gravitational Relaxation of The Cosmological Constant. https://doi.org/10.1016/j.physletb.2005.09.026

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