Localized U(1) Gauge Fields, Millicharged Particles, and Holography
Abstract
We consider U(1) gauge fields in a slice of AdS_5 with bulk and boundary mass parameters. The zero mode of a bulk U(1) gauge field can be localized either on the UV or IR brane. This leads to a simple model of millicharged particles in which fermions can have arbitrarily small electric charge. In the electroweak sector we also discuss phenomenological implications of a localized U(1)_Y gauge boson. Using the AdS/CFT correspondence we present the 4D holographic interpretation of the 5D model. In particular the photon is shown to be a composite particle when localized near the IR brane, whereas it is elementary when localized near the UV brane. In the dual interpretation the ``millicharge'' results from an elementary fermion coupling to a composite photon via a vector current with large anomalous dimension.
Cite
@article{arxiv.hep-ph/0512356,
title = {Localized U(1) Gauge Fields, Millicharged Particles, and Holography},
author = {Brian Batell and Tony Gherghetta},
journal= {arXiv preprint arXiv:hep-ph/0512356},
year = {2008}
}
Comments
26 pages, 1 figure