Looking Beyond the Standard Model, From Particle Physics to Cosmology

University Of Arizona, Tucson AZ

Investigators

Abstract

The PI proposes to study aspects of particle physics beyond the standard model that will potentially be tested within the next decade, and that may fill some of the gaps in our current understanding of particle physics and cosmology. The PI has proposed several new ideas which deserve exploration This proposal focuses on studying aspects of Supersymmetry, Higgs physics and the possible role of extra dimensions, all of which will be studied in upcoming collider experiments at the LHC, or possibly even at the Tevatron. The PI also proposes to study the interplay of neutrino physics and cosmology, a timely endeavor now that observational cosmology and the various neutrino experiments have posed certain puzzles in the neutrino sector that require explanation. The major part of the proposal is devoted to supersymmetric extensions of the standard model. First there is a plan to improve a theory with an interesting pattern of the soft-breaking terms, in which the gauginos obtain Dirac masses, rather than the usual Majorana masses. Such scenario faces several tight experimental constraints. The second project concerns the fine-tuning associated with the bounds on the Higgs mass. A theory that is less fine tuned might be obtained by using little Higgs mechanism that operates at low energies after supersymmetry is broken. The third project proposes to increase the upper bound on the mass of the lightest Higgs particle in the minimal supersymmetric standard model.