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arXiv · 1505.00057

Can Galileons solve the muon problem?

Henry Lamm
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Abstract

The leptonic bound states positronium and muonium are used to constrain galileon contributions to the Lamb shift of muonic hydrogen. Through the application of a variety of bounds on lepton compositeness, it is shown that either the assumption of equating the charge radius of a particle with its galileon scale radius is incompatible with experiments or the scale of galileons must be $M>1.33$ GeV, too large to solve the muon problem. The possibility of stronger constraints in the future from true muonium are discussed.

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Henry Lamm. 2015-04-30. Can Galileons solve the muon problem?. https://doi.org/10.1103/physrevd.92.055007

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