English

Conserved quantities and regularity in fluid dynamics

Analysis of PDEs 2020-03-18 v1 Fluid Dynamics

Abstract

Conserved or dissipated quantities, like energy or entropy, are at the heart of the study of many classes of time-dependent PDEs in connection with fluid mechanics. This is the case, for instance, for the Euler and Navier-Stokes equations, for systems of conservation laws, and for transport equations. In all these cases, a formally conserved quantity may no longer be constant in time for a weak solution at low regularity. The delicate interplay between regularity and conservation of the respective quantity relates to renormalisation in the DiPerna-Lions theory of transport and continuity equations, and to Onsager's conjecture in the realm of ideal incompressible fluids. We will review the classical commutator methods of DiPerna-Lions and Constantin-E-Titi, and then proceed to more recent results.

Keywords

Cite

@article{arxiv.2003.07807,
  title  = {Conserved quantities and regularity in fluid dynamics},
  author = {Emil Wiedemann},
  journal= {arXiv preprint arXiv:2003.07807},
  year   = {2020}
}

Comments

This is a set of lecture notes for the 2019 EMS School in Applied Mathematics held in K\'acov, Czech Republic. It partially contains previously uploaded material, in particular from arXiv:1412.2476

R2 v1 2026-06-23T14:17:38.654Z