UV-completion by classicalization

  • Gia Dvali
  • Gian F. Giudice
  • Cesar Gomez
  • Alex Kehagias
Open Access


We suggest a novel approach to UV-completion of a class of non-renormalizable theories, according to which the high-energy scattering amplitudes get unitarized by production of extended classical objects (classicalons), playing a role analogous to black holes, in the case of non-gravitational theories. The key property of classicalization is the existence of a classicalizer field that couples to energy-momentum sources. Such localized sources are excited in high-energy scattering processes and lead to the formation of classicalons. Two kinds of natural classicalizers are Nambu-Gold stone bosons (or, equivalently, longitudinal polarizations of massive gauge fields) and scalars coupled to energy-momentum type sources. Classicalization has interesting phenomenological applications for the UVcompletion of the Standard Model both with or without the Higgs. In the Higgless Standard Model the high-energy scattering amplitudes of longitudinal W -bosons self-unitarize via classicalization, without the help of any new weakly-coupled physics. Alternatively, in the presence of a Higgs boson, classicalization could explain the stabilization of the hierarchy. In both scenarios the high-energy scatterings are dominated by the formation of classicalons, which subsequently decay into many particle states. The experimental signatures at the LHC are quite distinctive, with sharp differences in the two cases.


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© The Author(s) 2011

Open Access This article is distributed under the terms of the Creative Commons Attribution License which permits any use, distribution and reproduction in any medium, provided the original author(s) and source are credited.

Authors and Affiliations

  • Gia Dvali
    • 1
    • 2
    • 3
    • 4
  • Gian F. Giudice
    • 3
  • Cesar Gomez
    • 5
  • Alex Kehagias
    • 6
  1. 1.Arnold Sommerfeld Center for Theoretical Physics, Fakultät für PhysikLudwig-Maximilians-Universität MünchenMünchenGermany
  2. 2.Max-Planck-Institut für PhysikMünchenGermany
  3. 3.CERN, Theory DivisionGeneva 23Switzerland
  4. 4.CCPP, Department of PhysicsNew York UniversityNew YorkU.S.A.
  5. 5.Instituto de Física Teórica UAM-CSIC, C-XVIUniversidad Autónoma de MadridMadridSpain
  6. 6.Physics DivisionNational Technical University of AthensAthensGreece

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