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arXiv · 0808.3977

The Soft-Wall Standard Model

Brian Batell·Tony Gherghetta·Daniel Sword
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Abstract

We explore the possibility of modeling electroweak physics in a warped extra dimension with a soft wall. The infrared boundary is replaced with a smoothly varying dilaton field that provides a dynamical spacetime cutoff. We analyze gravity, gauge fields, and fermions in the soft-wall background and obtain a discrete spectrum of Kaluza-Klein states which can exhibit linear Regge-like behavior. Bulk Yukawa interactions give rise to nonconstant fermion mass terms, leading to fermion localization in the soft-wall background and a possible explanation of the Standard Model flavor structure. Furthermore we construct electroweak models with custodial symmetry, where the gauge symmetry is broken with a bulk Higgs condensate. The electroweak constraints are not as stringent as in hard-wall models, allowing Kaluza-Klein masses of order the TeV scale.

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Brian Batell, Tony Gherghetta, Daniel Sword. 2008-08-28. The Soft-Wall Standard Model. https://doi.org/10.1103/physrevd.78.116011

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