Christopher T. Hill is an American theoretical physicist at the Fermi National Accelerator Laboratory who did undergraduate work in physics at M.I.T., and graduate work at Caltech. Hill's Ph.D. thesis, "Higgs Scalars and the Nonleptonic Weak Interactions" contains the first discussion of the two-Higgs-doublet model. Hill has made contributions to dynamical theories of electroweak symmetry breaking, and is an originator of the top quarkinfrared fixed point, top quark condensates, topcolor, and dimensional deconstruction. and has coauthored an extensive review of strong dynamical theories. He is also an originator of cosmological models of dark energy and dark matter based upon ultra-low mass bosons associated with neutrino masses and was first to propose that the cosmological constant is connected to the neutrino mass, as. He has also developed modern theories of the origin of ultra-high-energy nucleons and neutrinos from grand unification relics, such as cosmic strings. Hill has made significant contributions to the theory of heavy-light mesons, which contain a heavy quark and a light anti-quark, and are systems that display a remarkable chiral dynamics. With coauthors, he developed the theory and correctly predicted an abnormally long-lived resonance, the and numerous decay modes which have been confirmed by experiment. More recently he has focused on the idea that all fundamental mass scales may be associated with spontaneously broken scale symmetry, or. The scale of gravity and the inflationary phase of the ultra-early universe may be generated together as part of a unified phenomenon dubbed "inertial symmetry breaking." Hill has recently speculated that Higgs bosons are composite objects held together by gravitation. Gravity can form mini black holescomposed of ordinary quarks and leptons with the properties required by Higgs bosons, but very heavy. Quantum effects can make these states very light and they may then play the role of the standard model Higgs boson. In this picture, the observed Higgs boson is a top anti-top quark bound state, and the theory predicts the existence of many sequential, heavier Higgs bosons, with "large" coupling constants to quarks and leptons. This may explain the puzzle of the many small parameters in the standard model. Several of these new heavy Higgs bosons may be accessible to the LHC in processes like .
