I'm trying to teach myself the Composite Higgs Model, both its theory and its LHC phenomenology (particularly the 4DCHM). Unfortunately, I'm struggling; the literature is contradictory and/or omits basic details (?!). I have a few related questions, that should help me get started understanding the models,
- What are the extra symmetry groups in the 4DCHM/minimal CHM? Is the $SO(5)/SO(4)$ approximate symmetry global or local? If it is local (as this source suggests hep-ph/1302.2371v2), why aren't the Goldstone bosons (the four Higgs dof) eaten by the broken generators?
- What is the extra field content in the 4DCHM/minimal CHM? What extra gauge or fermion fields are present? Are they composite from the strong dynamics or fundamental?
- How are the SM, new fundamental, new composite and new gauge fields arranged into representations of the extra symmetry groups?
Any help or sources of information would be appreciated.