ICM 2026 Invited Section Lecture - Mariusz Mirek

ICM 2026 Invited Section Lecture - Mariusz Mirek

Formal & Physical Sciences Mathematics PBMathematics
🎙 Mariusz Mirek 👥 61K 📅 September 28, 2026 ⏱ 40 min 👁 264 📄 expert opinion 🧭 2026-10-06
Available in: English (current) Français

Keywords

circle methodpointwise ergodic theoremsequidistributionWeyl sumspolynomial averages

Summary

This lecture by Mariusz Mirek, given at an ICM 2026 invited section, explores the circle method and its quantitative role in understanding pointwise almost everywhere convergence for polynomial ergodic averaging operators. Mirek begins with the historical origins of the circle method in the work of Hardy, Ramanujan, and Littlewood on Waring’s problem. He then introduces Weyl’s criterion for equidistribution and demonstrates its application to irrational rotations and polynomial sequences, highlighting the Weyl differencing technique. The lecture bridges number theory and ergodic theory by presenting Bourgain’s use of the circle method to prove pointwise convergence for polynomial averages, and discusses the distinction between norm and pointwise convergence. Mirek surveys various sequences that are Lp-good or Lp-bad, including the resolution of Rosenblatt’s conjecture. He also covers multilinear ergodic averages, Furstenberg’s correspondence principle, and the Bergelson-Leibman theorem for polynomial patterns. The talk concludes by presenting the current state of the Furstenberg-Bergelson-Leibman conjecture and open problems regarding limits of such averages.

157 words

Critical Evaluation

Value of the Information & Strength of the Argument

The lecture offers substantial value by synthesizing deep connections between analytic number theory and ergodic theory. Mirek argues persuasively that quantitative methods, such as the circle method, are not merely tools but can fundamentally shape the understanding of pointwise convergence phenomena. The argumentation is rigorous, with step-by-step derivations of key estimates, such as Weyl’s inequality and its functional-analytic formulation. The presentation of Bourgain’s breakthrough illustrates how these techniques resolve long-standing problems. The lecturer also stresses that the methods themselves can be more intriguing than the initial problem, a point reinforced by the various generalizations and open questions he highlights.

Scientific Rigor, Source Quality, Title Accuracy

The lecture is scientifically rigorous, rooted in well-established literature. Mirek correctly attributes results to their sources, including Weyl, Sierpinski, Birkhoff, Khinchin, Bellow, Bourgain, Furstenberg, Bergelson, Leibman, and others, without misrepresenting their contributions. The mathematical derivations are accurate and consistent with the field’s current understanding. The title is appropriate: it accurately indicates the speaker and the topic, and the content matches the advertised subject. No external sources or URLs were provided in the description, but the oral citations are credible and traceable.

195 words

Title / Content Match

The title accurately reflects the content: an invited lecture by Mariusz Mirek on the circle method and its role in pointwise ergodic theorems.

Quality & Reliability

8/10

Lecture by a leading researcher at an ICM invited session, based on established methods and results from analytic number theory and ergodic theory. The technical content is rigorous and consistent with known literature.

Key Moments

Contribution & Novelties

The lecture provides a unifying perspective on how the circle method, originally developed for number theory, is applied to ergodic theory to establish pointwise convergence results. Mirek emphasizes the interplay between quantitative estimates and qualitative convergence phenomena, highlighting that the methods themselves can be more profound than the solutions. He presents recent developments, including his own work on pointwise convergence for multilinear averages, and outlines open conjectures. The talk is valuable for researchers seeking to understand the current frontiers of these fields.

Pour aller plus loin :

  • Circle method — The fundamental analytic technique used in additive number theory, central to this lecture.
  • Weyl’s criterion — A key equivalence for equidistribution of sequences, used extensively in the talk.
  • Pointwise ergodic theorem — The context for studying almost everywhere convergence of ergodic averages.
  • Bourgain’s pointwise ergodic theorem — Overview of Bourgain’s work that brought the circle method into ergodic theory.

149 words

Radar Profile

The scores reflect an extremely technical and dense lecture, with notably high level of technical detail (9) and strong quality and quantity of information (8 each). The global reliability is also high (8), indicating a trustworthy expert source. The profile suggests that the content is sophisticated and primarily aimed at a specialized mathematical audience, with a balanced emphasis on both information density and quality.

Reliability 8/10