Date Awarded


Document Type


Degree Name

Doctor of Philosophy (Ph.D.)




Bill Cooke


In this dissertation we address three issues related to physics beyond the Standard model: flavor and the use of discrete gauge symmetries, the dynamical breaking of electroweak symmetry, and the addition of a U(1) gauge symmetry to the Standard model in order to suppress proton decay. We present: (i) A model of flavor based on the double tetrahedral group that leads to acceptable quark and lepton masses as well as mixing angles. Furthermore it gives solutions for the atmospheric and solar neutrino problems. (ii) A model of bosonic topcolor in which the breaking of electroweak symmetry occurs dynamically through the vacuum expectation value of a composite field, generated by some strong dynamics that affects third generation fields only. The mass of the top quark is also generated by this vev. All other light quarks acquire their masses through the vev of a fundamental scalar also present in the theory. (iii) Models in which baryon number has been gauged to eliminate operators that lead to rapid proton decay. We study the phenomenology of the gauge boson associated with the new U(1). In one model we investigate the possibility of having a light leptophobic gauge boson with mass in the 1--10 GeV range. In another model, constructed in the framework of extra dimensions, we explore the phenomenology of the leptophobic gauge boson and its Kaluza-Klein excitations.



© The Author

Included in

Physics Commons