# Events for 04/25/2023 from all calendars

## Nonlinear Partial Differential Equations

**Time: ** 3:00PM - 4:00PM

**Location: ** BLOC 302

**Speaker: **Juhi Jang, University of Southern California

**Title: ***Dynamics of Newtonian stars *

**Abstract: **A classical model to describe the dynamics of Newtonian stars is the gravitational Euler-Poisson system. The Euler-Poisson system admits a wide range of star solutions that are in equilibrium or expand for all time or collapse in a finite time or rotate. In this talk, I will discuss some recent progress on those star solutions with focus on expansion and collapse. If time permits, I will also discuss the non-radial stability of self-similarly expanding Goldreich-Weber star solutions.

## Noncommutative Geometry Seminar

**Time: ** 4:00PM - 5:00PM

**Location: ** BLOC 302

**Speaker: **Yasuyuki Kawahigashi, University of Tokyo

**Title: ***(Colloquium) Quantum symmetries in operator algebras and mathematical physics*

**Abstract: **A notion of symmetry is fundamental in mathematics and physics. A new type of "quantum" symmetry has emerged in operator algebras, quantum groups, quantum invariants in low dimensional topology, integrable systems, vertex operator algebras, quantum field theory and condensed matter physics since 1980's. I will present development in these areas from an operator algebraic viewpoint. Emphasis is given to the Jones theory of subfactors, chiral conformal field theory and two-dimensional topological order. No knowledge on these topics is assumed as a prerequisite.

## Colloquium

**Time: ** 4:00PM - 5:00PM

**Location: ** Bloc 302

**Speaker: **Yasu Kawahigashi, Tokyo University

**Description: **Title: Quantum symmetries in operator algebras and mathematical physics

Abstract: A notion of symmetry is fundamental in mathematics and physics.
A new type of "quantum" symmetry has emerged in operator algebras, quantum
groups, quantum invariants in low dimensional topology, integrable systems,
vertex operator algebras, quantum field theory and condensed matter physics
since 1980's. I will present development in these areas from an operator
algebraic viewpoint. Emphasis is given to the Jones theory of subfactors,
chiral conformal field theory and two-dimensional topological order. No
knowledge on these topics is assumed as a prerequisite.