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We develop a new method for bosonizing the Fermi surface. In this method, a system with a Fermi surface is described as a coadjoint orbit of the group of canonical transformations. The method naturally parametrizes the Fermi surface by a bosonic field that depends on the spacetime coordinates and the position on the Fermi surface. The Wess-Zumino-Witten term in the effective action, governing the adiabatic phase acquired when the Fermi surface changes its shape, is completely fixed by the Kirillov-Kostant-Souriau symplectic form on the coadjoint orbit. We show that the resulting local effective field theory captures both linear and nonlinear effects in Landau’s Fermi liquid theory. Possible extensions of the theory are described.  Reference: arXiv:2203.05004.

Zoom Link: https://pitp.zoom.us/j/95453440138?pwd=b0Fmbi9HTU9nYTA3Y2F6dWlha294UT09

I will describe 4pt conformal blocks for scalar operators in diverse dimensions by using a single unified formalism, and explain a property of the conformal blocks known as stability. This stability implies that when writing conformal blocks as certain multivariate series, the coefficients of this expansion only depend on Young diagrams. In particular, we can bosonise the conformal computation and simply focus on compact groups. In this framework the blocks are polynomials of the BC root system after we apply complementation. I will then explain the connection with mathematics and show how to formulate a superconformal Cauchy identity which yields the CPW of any free theory diagram in any dimension. For discussion, I will finally mention q-deformations results.

Zoom Link: https://pitp.zoom.us/j/96912692269?pwd=TE8vT01mam9lQjhVV3VSYUtWR2d5Zz09

I review the main mechanisms that convert fundamental CP-violating parameters (theta_QCD and Kobayashi-Maskawa phase) to the observable electric dipole moments (EDMs). Given recent progress, the EDMs connected to electron spin (paramagnetic EDMs) are calculated. The limit on QCD theta angle is 3 * 10^(-8) and  somewhat subdominant to neutron EDM, but can be improved. The Kobayashi-Maskawa phase contributes to paramagnetic EDMs at the level of 10^{-35} e cm in units of equivalent electron EDM, which is much larger than what was previously expected.  

Zoom Link: https://pitp.zoom.us/j/96502704646?pwd=ZThQWGU2dEZPWjdPQnp2ZEpPVXRIdz09

This course will introduce some advanced topics in general relativity related to describing gravity in the strong field and dynamical regime. Topics covered include properties of spinning black holes, black hole thermodynamics and energy extraction, how to define horizons in a dynamical setting, formulations of the Einstein equations as constraint and evolution equations, and gravitational waves and how they are sourced.