A Peculiar Dynamically Warped Theory Space

We study a supersymmetric deconstructed gauge theory in which a warp factor emerges dynamically, driven by Fayet-Iliopoulos terms. The model is peculiar in that it possesses a global supersymmetry that remains unbroken despite nonvanishing D-term vacuum expectation values. Inclusion of gravity and/or additional messenger fields leads to the collective breaking of supersymmetry and to an unusual phenomenology.Comment: 4 pages LaTeX, Presented at SUSY06, the 14th International Conference on Supersymmetry and the Unification of Fundamental Interactions, Irvine, California, USA 12-17 June 200

Electroweak Constraints on Extended Models with Extra Dimensions

Electroweak measurements place significant bounds on higher-dimensional versions of the standard model in which the gauge and Higgs fields have Kaluza-Klein excitations. These bounds may be altered quantitatively if chiral matter is also allowed to propagate in the higher-dimensional `bulk'. We determine the electroweak constraints on a number of models of this type, including scenarios in which only the leptons or only the first two generations of matter fields propagate in the bulk. We also consider the possibility that different factors of the electroweak gauge group may be distinguished by their bulk/three-brane assignment, and study a minimal extra-dimensional Z' model. We find typical bounds on the compactification scale between 1.5 and 4 TeV, and comment on models in which these bounds might be significantly relaxed.Comment: 15 pages Revtex, 1 EPS figur

Pseudo-Familon Dark Matter

Motivated by a model of pseudo-Majoron dark matter, we show how the breaking of a global symmetry that acts nontrivially in lepton generation space can lead to a viable pseudo-familon dark matter candidate. Unlike the pseudo-Majoron, the pseudo-familon in our model decays primarily to charged leptons and can account for the excess observed in the cosmic ray electron and positron spectra.Comment: 12 pages LaTeX, 1 figur

Orbitally Excited Baryons in Large N_c QCD

We present a model-independent analysis of the mass spectrum of nonstrange l=1 baryons in large N_c QCD. The 1/N_c expansion is used to select and order a basis of effective operators that spans the nine observables (seven masses and two mixing angles). Comparison to the data provides support for the validity of the 1/N_c expansion, but also reveals that only a few nontrivial operators are strongly preferred. We show that our results have a consistent interpretation in a constituent quark model with pseudoscalar meson exchange interactions.Comment: 4 pages LaTeX. Invited parallel session talk presented at the XVth Particles and Nuclei International Conference (PANIC99), June 10, 1999, Uppsala, Swede

Bosonic Topcolor

A topcolor model is presented that contains both composite and fundamental scalar fields. Strong dynamics accounts for most of the top quark mass and part of the electroweak symmetry breaking scale. The fundamental scalar is weakly coupled and transmits its share of electroweak symmetry breaking to the light fermions. The model is allowed by the current experimental bounds, and can give a potentially large contribution to $D^0-\bar{D^0}$ mixing.Comment: Talk given by A. Aranda at DPF 2000, Ohio State, August 200