Theory Division

The η meson is almost unique in the particle universe since it is a Goldstone boson and the dynamics of its decay are strongly constrained.  Because the eta has no charge, decays that violate conservation laws can occur without interfering with a corresponding current. The integrated eta meson samples collected in earlier experiments have been less than... More »

Type Ia Supernovae continue to prove to be an incredibly useful tool to measure cosmic distances.  They are a critical pillar in the measurement of the local value of the Hubble constant, which has now been shown to be in over 3-sigma tension with the inferred value of the Hubble constant from measurements of the... More »

The simplest extension of the Standard Model is to add a gauge singlet scalar: the singlet extended Standard Model.  Although simple, this model is quite well-motivated and has an interesting phenomenology.  Of particular interest is that this model can provide a mechanism for the strong first order phase transition necessary for electroweak baryogenesis. In this... More »

The theory of Quantum Electrodynamics in three dimensions (QED3) has received considerable attention due to its applications in condensed matter physics and due to its similarities with stongly coupled QCD-like theories in four dimensions. QED3 is strongly coupled at energies close to the gauge coupling that in this case is dimensionful. Whereas for a large... More »

Daniel Bowring, Dielectric Tuning of Cavities Bob Zwaska, Sinuous Target Angela Fava, Liquid Argon Charge Amplification Device Javier Tiffenberg, Low Energy Threshold Particle Detector

Nature comes to us with many hierarchies of scale, and science progresses because we do not need to understand them all at once. Effective theories exploit this fact to isolate what is important at any scale. This talk summarizes how effective theories work for applications to the ordinary and relativistic quantum mechanics of a particle... More »