Title: Classical and Quantum stability in theories with many fields Abstract: In landscape models, one typically studies and effective potential for many fields, examining stationary points. There has been some work on the likelihood that a particular stationary point is classically stable, and somewhat less on quantum stability. Some of the results, as we will explain, are puzzling. We will … Read More

Title: The Unnatural Composite Higgs Abstract: A simple way to trivially satisfy precision-electroweak and flavor constraints in composite Higgs models is to require a large global symmetry breaking scale, f > 10 TeV. This leads to a tuning of order 10^-4 to obtain the observed Higgs mass, but gives rise to a ‘split’ spectrum where the strong-sector resonances with masses … Read More

Abstract: Soft-Collinear Effective Theory (SCET) is a framework for modeling the infrared structure of theories whose long distance behavior is dominated by soft and collinear divergences. I will demonstrate that SCET can be made compatible with supersymmetry (SUSY), explicitly with N = 1 SUSY Yang-Mills. For contrast arguments will be given that chiral SUSY theories with Yukawa couplings, specifically the … Read More

Abstract: Light dark matter scattering in a crystal or fluid must recoil off a collective excitation (phonon) rather than off individual nuclei. I will set up the appropriate low energy effective theory and show how density functional theory (DFT) methods can be used to calculate the dark matter scattering rate for various dark matter models and target materials.

ABSTRACT: Halometry—mapping out the spectrum, location, and kinematics of nonluminous structures inside the Galactic halo—can be realized via effects that variable weak gravitational lensing induces on the proper motions of stars and other luminous background sources. Modern astrometric surveys provide unprecedented positional precision along with a leap in the number of cataloged objects. Astrometry thus offers a new and sensitive … Read More