Blaschke operations on log-concave functions and affine isoperimetric inequalities

Fuente: arXiv
Saved in:
Bibliographic Details
Main Authors: Chasioti, Effrosyni, Hoehner, Steven
Format: Preprint
Published: 2026
Subjects:
Online Access:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866913137477812224
author Chasioti, Effrosyni
Hoehner, Steven
author_facet Chasioti, Effrosyni
Hoehner, Steven
contents We introduce Blaschke addition and homothety operations on log-concave functions and study their affine-geometric consequences. Our starting point is the first variation formula of Falah and Rotem (Calc. Var. and PDE, 2026), which associates to each log-concave function a pair of surface area measures. Using the additivity of these measures, we define a canonical Blaschke sum and Blaschke homothety on the class of log-concave functions, uniquely determined up to translation. We establish the basic algebraic properties of these operations, define the associated Blaschke symmetral, and show that this symmetrization preserves both total mass and the first quermassintegral. We also prove that successive Blaschke symmetrizations converge, after translations, to a radially symmetric log-concave function, which we call the mean Blaschke symmetral. We then relate the canonical theory to projection-type constructions. In particular, we show that the functional projection body arising from the first variation coincides with the projection body of the asymmetric LYZ body, and we derive corresponding intertwining properties. As applications, we prove concavity of the entropy with respect to the canonical Blaschke sum and obtain associated Kneser--Süss-type inequalities. We also study a functional version of affine surface area, and prove affine isoperimetric inequalities for log-concave functions. In particular, we obtain a Blaschke-concavity property for the affine surface area and show that it is maximized, under fixed first quermassintegral, by radially symmetric functions.
format Preprint
id arxiv_https___arxiv_org_abs_2605_17688
institution arXiv
publishDate 2026
record_format arxiv
spellingShingle Blaschke operations on log-concave functions and affine isoperimetric inequalities
Chasioti, Effrosyni
Hoehner, Steven
Functional Analysis
Metric Geometry
52A40 (Primary) 52A39, 52A41 (Secondary)
We introduce Blaschke addition and homothety operations on log-concave functions and study their affine-geometric consequences. Our starting point is the first variation formula of Falah and Rotem (Calc. Var. and PDE, 2026), which associates to each log-concave function a pair of surface area measures. Using the additivity of these measures, we define a canonical Blaschke sum and Blaschke homothety on the class of log-concave functions, uniquely determined up to translation. We establish the basic algebraic properties of these operations, define the associated Blaschke symmetral, and show that this symmetrization preserves both total mass and the first quermassintegral. We also prove that successive Blaschke symmetrizations converge, after translations, to a radially symmetric log-concave function, which we call the mean Blaschke symmetral. We then relate the canonical theory to projection-type constructions. In particular, we show that the functional projection body arising from the first variation coincides with the projection body of the asymmetric LYZ body, and we derive corresponding intertwining properties. As applications, we prove concavity of the entropy with respect to the canonical Blaschke sum and obtain associated Kneser--Süss-type inequalities. We also study a functional version of affine surface area, and prove affine isoperimetric inequalities for log-concave functions. In particular, we obtain a Blaschke-concavity property for the affine surface area and show that it is maximized, under fixed first quermassintegral, by radially symmetric functions.
title Blaschke operations on log-concave functions and affine isoperimetric inequalities
topic Functional Analysis
Metric Geometry
52A40 (Primary) 52A39, 52A41 (Secondary)
url https://arxiv.org/abs/2605.17688