2004/05/31 by Riccardo Barbieri, Alex Pomarol, Riccardo Rattazzi +2 · 26 citations
Computer Science · Physics and Astronomy · #Computational Physics and Python Applications #Cosmology and Gravitation Theories #Electroweak interaction #Gauge boson #Gauge theory #Particle physics #Particle physics theoretical and experimental studies #Physics #Symmetry breaking #Technicolor #hep-ph
paper · pdf · doi:10.1016/j.nuclphysb.2004.10.014
published as Nucl.Phys.B703:127-146,2004 · 16 pages, 5 figures. Ref.s added, discussion of low energy observables improved
arxiv created 2004/07/19 · openalex publication_date 2004/10/23 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
In a generic 'universal' theory of electroweak symmetry breaking, non fine-tuned heavy new physics affects the low-energy data through four parameters, which include and properly extend the generally insufficient S and T. Only by adding the LEP2 data to the global electroweak fit, can all these four form factors be determined and deviations from the SM be strongly constrained. Several of the recently proposed models (little Higgs, gauge bosons in extra dimensions or Higgsless models in 5D) are recognized to be 'universal' in a straightforward way after a proper definition of the effective vector boson fields. Among various applications, we show that proposed Higgsless models in 5D, when calculable, do not provide a viable description of electroweak symmetry breaking in their full range of parameters.