cff-version: 1.2.0 message: >- If you use this formalization, please cite it as below. Scott Armstrong was supported by the European Research Council (ERC) under the European Union's Horizon Europe research and innovation programme, grant agreement No. 101200828. title: "EscauriazaSereginSverak: a Lean 4 formalization of the Escauriaza-Seregin-Sverak theorem for the Navier-Stokes equations" version: "1.0" date-released: 2026-09-29 abstract: >- A machine-checked Lean 4 / Mathlib formalization, built on the published Caffarelli-Kohn-Nirenberg formalization (which contains Leray's global existence theorem in suitable form, its singular-set corollary, the associated pressure and the forced versions, all used here), of the Escauriaza-Seregin-Sverak theorem on the three-dimensional incompressible Navier-Stokes equations on R^3: a Leray-Hopf solution bounded in L^infinity(0,T;L^3) has no singular points, lies in L^5, is unique among Leray-Hopf solutions with the same datum and is smooth on R^3 x (0,T], so that Theorem 1.3 of that paper is proved in full; this rests on the Ladyzhenskaya-Prodi-Serrin theorem, also formalized: a Leray-Hopf solution in L^l(0,T;L^s) with 3/s + 2/l = 1 and 3 < s <= infinity is unique and smooth on R^3 x (0,T]; the combined regularity criterion for 3 <= s <= infinity is stated as a single theorem. Also included are the local L^3 regularity theorem and the unique-continuation, backward-uniqueness and Carleman theorems it rests on. Each of the ten theorems is proved using only the standard axioms and is restated in a Mathlib-only comparator challenge that is checked separately. type: software authors: - family-names: Armstrong given-names: Scott affiliation: "CNRS and Laboratoire Jacques-Louis Lions, Sorbonne Université; Courant Institute School of Mathematics, Computing, and Data Science, New York University" keywords: - Lean - mathlib - formal verification - Navier-Stokes equations - Leray-Hopf solutions - suitable weak solutions - backward uniqueness - Escauriaza-Seregin-Sverak - Ladyzhenskaya-Prodi-Serrin license: Apache-2.0 repository-code: "https://github.com/scottnarmstrong/EscauriazaSereginSverak" references: - type: unpublished title: "The Escauriaza-Seregin-Sverak theorem" authors: - family-names: Armstrong given-names: Scott - type: software title: "CaffarelliKohnNirenberg: a Lean 4 formalization of the Caffarelli-Kohn-Nirenberg partial regularity theorem for the Navier-Stokes equations" authors: - family-names: Armstrong given-names: Scott - family-names: Vicol given-names: Vlad repository-code: "https://github.com/scottnarmstrong/CaffarelliKohnNirenberg" - type: article title: "L_{3,infinity}-solutions of Navier-Stokes equations and backward uniqueness" authors: - family-names: Escauriaza given-names: L. - family-names: Seregin given-names: G. A. - family-names: Sverak given-names: V. journal: "Russian Mathematical Surveys" volume: 58 issue: 2 start: 211 end: 250 year: 2003 doi: "10.1070/RM2003v058n02ABEH000609"