ICM 2026 Invited Section Lecture - Maria Colombo

ICM 2026 Invited Section Lecture - Maria Colombo

Formal & Physical Sciences Mathematics PBMathematics
🎙 Maria Colombo 👥 61K 📅 September 28, 2026 ⏱ 47 min 👁 293 📄 expert opinion 🧭 2026-10-06
Available in: English (current) Français

Keywords

weak solutionsnon-uniquenessinstabilityconvex integrationself-similarity

Summary

The lecture by Maria Colombo, invited for ICM 2026, provides an overview of recent progress on the non-uniqueness of weak solutions for the Euler and Navier-Stokes equations. Beginning with fundamental properties such as energy conservation and scaling, she introduces the concept of distributional solutions and the global energy inequality. The focus then shifts to a theorem with Albritton and Bru showing non-uniqueness for Navier-Stokes with a body force, based on constructing linear instability in similarity variables. The talk also covers the 2D Euler vorticity formulation, the Yudovich uniqueness theorem, and convex integration approaches including the Onsager conjecture. Vishik’s earlier non-uniqueness results are presented, along with a method to lift 2D instabilities to 3D. Open questions on vanishing viscosity limits, anomalous dissipation, and passive scalars are discussed, concluding with a generic result on ordinary differential equation uniqueness for random velocity fields.

140 words

Critical Evaluation

Value of the Information & Strength of the Argument

The lecture provides a comprehensive and high-level synthesis of the current state of the art in non-uniqueness for fluid PDEs. The argumentation is rigorous, presenting both classical results and recent breakthroughs, often with sketches of proofs and conceptual insights. The speaker carefully distinguishes proven theorems from conjectures and numerical evidence, linking mathematical theory to physical intuition. The value lies in its clear organization and the way it connects diverse techniques—convex integration, linear instability, self-similarity—under a unified perspective. The evidence presented is solid, with careful attention to technical hypotheses and the role of body forces or initial conditions.

Scientific Rigor, Source Quality, Title Accuracy

The scientific rigor is outstanding, as expected from an ICM invited lecture. The speaker cites numerous works by herself and others (Albritton, Bru, Vishik, Onsager, Yudovich, etc.) without providing explicit URLs, which is typical for a talk. The title is merely a formal identification; it does not misrepresent the content but also does not indicate the topic. The lecture is logically structured and adheres to mathematical precision, with careful definitions and explicit statements of theorems and conjectures. No external sources are provided in the description, so the analysis relies solely on the talk itself.

206 words

Title / Content Match

The title is generic, identifying the lecture and author but not the specific topic. It is not misleading, but it does not convey the mathematical content.

Quality & Reliability

9/10

The lecture is delivered by a leading researcher in the field, presenting peer-reviewed results and current research. The content is technically rigorous, well-structured, and reflects deep expertise in mathematical fluid dynamics.

Key Moments

Contribution & Novelties

The lecture synthesizes multiple recent developments, highlighting the speaker’s own contributions to non-uniqueness for Navier-Stokes with a body force and the transfer of instabilities from 2D to 3D. It offers a clear taxonomy of approaches—convex integration, linear instability, self-similarity—and outlines open problems concerning vanishing viscosity limits and anomalous dissipation. The talk also presents a new constructive perspective on generic uniqueness for ordinary differential equations driven by random fields.

Pour aller plus loin :

  • Navier–Stokes existence and smoothness — Discusses the millennium prize problem and the state of uniqueness and regularity for the 3D Navier-Stokes equations.
  • Convex integration — A key technique used to construct nonunique weak solutions to the Euler equations, crucial for the Onsager conjecture.
  • Onsager conjecture — The conjecture that non-conservation of energy is related to the regularity of solutions, with recent proofs by convex integration methods.

139 words

Radar Profile

The profile shows very high scores in technical level and information quality, with slightly lower but still strong marks for information quantity and global reliability. This indicates a dense, rigorous, and highly specialized lecture suitable for an expert audience.

Reliability 9/10