Please note that the list below only shows forthcoming events, which may not include regular events that have not yet been entered for the forthcoming term. Please see the past events page for a list of all seminar series that the department has on offer.

 

Past events in this series


Thu, 12 Nov 2026

12:00 - 13:00
C5

Uniform Integrability and the Problem of Pressure Formation for Euler-Riesz Systems

Athanasios Tzavaras
(KAUST)
Abstract
We consider the system of compressible Euler equations augmented with a nonlocal term associated to a Riesz potential. This system emerges as a critical point of an action functional. Also it is equipped with a stress tensor that may be expressed in two distinct representations and gives rise to an associated bilinear fractional integral operator. (i)  We establish a uniform estimate for a bilinear fractional integral operator via restricted weak-type endpoint estimates and  Marcinkiewicz interpolation. The estimate leads to integrability analysis of the associated stress-tensor. (ii)  Then we focus on the problem without a pressure term and examine the question of whether the nonlocal interaction can give rise to a pressure estimated in a Lebesgue space.  We use both the energy and a quantity proposed by the compensated integrability method. This gives rises to interesting analytical questions on lower bounds of functionals that will be reviewed. 
 
Joint work with N. Alves (KAUST) and L. Grafakos (Univ. of Missouri).
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Thu, 19 Nov 2026

12:00 - 13:00
C5

On the symmetric Morrey problem in three dimensions

Florian Gammer
(University of Regensburg)
Abstract

The existence of minimizers in the calculus of variations is closely tied to various notions of convexity. A fundamental question in this regard is how these notions relate to each other. 

In this talk, we study several such generalized notions of convexity for continuous integrands on the space of symmetric $3\times 3$ matrices and establish their mutual relationships.

In particular, we construct a symmetric quasiconvex integrand that is not polyconvex at symmetric matrices, and an integrand that is both symmetric rank-one convex and Hessian quasiconvex but not symmetric quasiconvex. We also establish a transfer principle that converts smooth rank-one convex functions that fail to be Hessian quasiconvex into symmetric rank-one convex integrands while preserving this failure. Applying this scheme to existing counterexamples, we obtain symmetric rank-one convex integrands that are not Hessian quasiconvex. Together with previous results, this settles all pairwise implications among the notions considered here.

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Thu, 03 Dec 2026

12:00 - 13:00
C5

TBA

Lisa Valentini
(DAMTP University of Cambridge)
Abstract

TBA

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