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arXiv · 0811.1163

Compact extra-dimensions as solution to the strong CP problem

F. L. Bezrukov·Y. Burnier
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Abstract

We show that the strong CP problem can, in principle, be solved dynamically by adding extra-dimensions with compact topology. To this aim we consider a toy model for QCD, which contains a vacuum angle and a strong CP like problem. We further consider a higher dimensional theory, which has a trivial vacuum structure and which reproduces the perturbative properties of the toy model in the low-energy limit. In the weak coupling regime, where our computations are valid, we show that the vacuum structure of the low-energy action is still trivial and the strong CP problem is solved. No axion-like particle occur in this setup and therefore it is not ruled out by astrophysical bounds.

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F. L. Bezrukov, Y. Burnier. 2009-09-08. Compact extra-dimensions as solution to the strong CP problem. https://doi.org/10.1103/physrevd.80.125004

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