2023/03/11 by Daniel Azagra, Azagra, Daniel, Anthony Cappello +3 · 1 citation
Computer Science · Mathematics · #26B25 #28A75 #41A30 #52A20 #52A27 #53C45 #Classical Analysis and ODEs (math.CA) #Differential Geometry (math.DG) #FOS: Mathematics #Functional Equations Stability Results #Mathematics and Applications #Optimization and Variational Analysis
paper · pdf · doi:10.48550/arxiv.2303.06265
openalex publication_date 2023/03/11 · openalex created_date 2023/03/16 · openalex updated_date 2026/07/28
We show a new, elementary and geometric proof of the classical Alexandrov theorem about the second order differentiability of convex functions. We also show new proofs of recent results about Lusin approximation of convex functions and convex bodies by C1,1 convex functions and convex bodies.