14.00 - 14.30: Natalia Pinzani-Fokeeva (KU Leuven)
14.40 - 15.10: Akash Jain (Victoria University)
15.10 - 15.40: Andrey Gromov (Brown University)
16.00-17.00 discussion moderated by Sergej Moroz
Title: From black holes to fluid membranes via Newton-Cartan geometry
Abstract: I will introduce the description of Newton-Cartan submanifolds and how that can be applied to fluid membranes and soap bubbles. I will explain how these models are related to relativistic models that describe the dynamics of higher-dimensional black holes.
Title: Enstrophy from symmetry
Abstract: Enstrophy is an approximately conserved quantity in 2+1 dimensional fluids, responsible for the inverse energy cascade in 2+1 dimensional turbulence.
Speaker: Akash Jain
Title: Effective field theory for non-Lorentzian hydrodynamics
Abstract: Hydrodynamics is a low-energy effective description of macroscopic systems fluctuating around thermal equilibrium. However, the conventional formulation of hydrodynamics, based on energy, momentum, and particle number conservation laws, is incomplete as it does not account for non-equilibrium stochastic fluctuations of the background thermal state. Over the last decade, a new formulation for relativistic hydrodynamics based on an effective action and symmetry principles has been developed. It provides a first-principle derivation of the hydrodynamic equations, along with a symmetry-based understanding of the local second law of thermodynamics. In this talk, we will discuss how these ideas can be expanded to non-Lorentzian hydrodynamics, in particular, Galilean hydrodynamics. We will introduce the relevant degrees of freedom and symmetries that can be systematically implemented to write down the effective action for non-Lorentzian hydrodynamics order-by-order in a derivative expansion. The talk will be based on arXiv:2008.03994 and arXiv:2010.15782.
Speaker: Andrey Gromov
Title: Fractons, conservation of multipole moments and tensor gauge theories
Abstract: I will introduce the (fundamentally non-relativistic) fracton phases of matter. Excitations supported by these phases are defined by their inability to freely propagate through space. Instead, the local excitations are either completely immobile or can move along submanifolds. Constraints on motion can be understood through the lens of symmetry, namely by enofrcing conservation of various multipole moments of charge density. This symmetry extends the algebra of spatial symmetries to the multipole algebra, that includes the generators of the multipole symmetry, which do not commute with the generators of translations and rotations. I will also discuss gauge theories obtained by gauging the multipole symmetry. The gauge fields obtained this way are not 1-forms. Rather, they are symmetric tensors, or, more generally, can transform in representations of the crystalline point groups.
