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arXiv · 2010.14028

Ghosts in the Wall

Christopher D. Carone
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Abstract

We consider the possibility of an axion-like particle (ALP) that is a ghost, with wrong-sign kinetic and mass terms. Such an ALP can arise as the partner to an ordinary particle in theories with higher-derivative quadratic terms. We compute the photon regeneration probability in light-shining-through-wall experiments and show that the presence of such a ghostly ALP can lead, in principle, to discernible effects.

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Christopher D. Carone. 2020-10-27. Ghosts in the Wall. https://doi.org/10.1103/physrevd.102.115039

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