2006/05/07 by Yasunori Nomura, David Poland, Brock Tweedie · 2 citations
Physics and Astronomy · #Black Holes and Theoretical Physics #Cosmology and Gravitation Theories #Particle physics theoretical and experimental studies #hep-ph #hep-th
paper · pdf · doi:10.1088/1126-6708/2006/12/002
published as JHEP 0612:002,2006 · 29 pages, references added
arxiv created 2006/05/07 · openalex publication_date 2006/12/01 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/01
We present a framework for grand unification in which the grand unified symmetry is broken spontaneously by strong gauge dynamics, and yet the physics at the unification scale is described by (weakly coupled) effective field theory. These theories are formulated, through the gauge/gravity correspondence, in truncated 5D warped spacetime with the UV and IR branes setting the Planck and unification scales, respectively. In most of these theories, the Higgs doublets arise as composite states of strong gauge dynamics, corresponding to degrees of freedom localized to the IR brane, and the observed hierarchies of quark and lepton masses and mixings are explained by the wavefunction profiles of these fields in the extra dimension. We present several realistic models in this framework. We focus on one in which the doublet-triplet splitting of the Higgs fields is realized within the dynamical sector by the pseudo-Goldstone mechanism, with the associated global symmetry corresponding to a bulk gauge symmetry in the 5D theory. Alternatively, the light Higgs doublets can arise as a result of dynamics on the IR brane, without being accompanied by their triplet partners. Gauge coupling unification and proton decay can be studied in these models using higher dimensional effective field theory. The framework also sets a stage for further studies of, e.g., proton decay, fermion masses, and supersymmetry breaking.