Heavy Flavor Theory

This is a limited review and update of the status of Heavy Flavor Physics. After we review the flavor problem we discuss a number of topics: recent puzzles in purely leptonic D and B decays and their possible resolutions, mixing in neutral B and D mesons, the determination of |Vcb| and |Vub| from semileptonic decays, and we conclude with radiative B decays.Comment: To be published in the proceedings of DPF-2009, Detroit, MI, July 2009, eConf C090726; v2: corrected statements about lattice results for exclusive B to pi semileptonic decay

Strong Electroweak Symmetry Breaking

Models of spontaneous breaking of electroweak symmetry by a strong interaction do not have fine tuning/hierarchy problem. They are conceptually elegant and use the only mechanism of spontaneous breaking of a gauge symmetry that is known to occur in nature. The simplest model, minimal technicolor with extended technicolor interactions, is appealing because one can calculate by scaling up from QCD. But it is ruled out on many counts: inappropriately low quark and lepton masses (or excessive FCNC), bad electroweak data fits, light scalar and vector states, etc. However, nature may not choose the minimal model and then we are stuck: except possibly through lattice simulations, we are unable to compute and test the models. In the LHC era it therefore makes sense to abandon specific models (of strong EW breaking) and concentrate on generic features that may indicate discovery. The Technicolor Straw Man is not a model but a parametrized search strategy inspired by a remarkable generic feature of walking technicolor, that technivector mesons are light, narrow and decay readily into electroweak vector mesons and photons. While walking technicolor is popular among practitioners, alternatives exist and the Straw Man may not lead to their discovery.Comment: Talk given at the XXIInd Rencontres de Blois, Loire, France, 16-20 July 201

What if? On the interplay between Serendipity, Intuition and Conjecture

While the Standard Model is in good shape, there are many reasons to believe it is incomplete. There are high expectations that the LHC will shed light on some well studied possibilities, like technicolor and supersymmetry. Emboldened by this optimism, we consider some non-mainstream ideas that if established would change dramatically the way we view the world.Comment: Talk give at the conference on Flavor Physics and CP Violation - FPCP 2010, May 25-29, 2010, Turin, Ital

FPCP Theory Overview

We first review some aspects of the determination of the sides and angles of the unitarity triangle. We pay particular attention to theory shortcomings, and present many alternative proposals for the determination of |Vub| (which at present is problematic). We then turn our attention to the more general question: What have we learned so far about flavor physics and where do we go from here? We argue that the aim of Flavor Physics should be to establish or rule out Minimal Flavor Violating interactions up to a scale of 10 TeV.Comment: Talk presented at Flavor Physics & CP Violation Conference, Bled, 2007; latex, 7 p