collaborators

6 papers

math.FA2026

Stability result for the extremal Grünbaum distance between convex bodies

Tomasz Kobos

In 1963 Grünbaum introduced the following variation of the Banach-Mazur distance for arbitrary convex bodies : $d_G(K, L) = \inf \{ |r| \ : \ K' \subset…

math.MG2026

Exact Banach-Mazur distances of certain -sums and cones

Florian Grundbacher, Tomasz Kobos

We determine certain Banach-Mazur distances involving -direct sums of finite-dimensional real normed spaces and related cone constructions of convex bodies. Using a recent…

math.MG2026

John-type decompositions for affinely-optimal positions of convex bodies

Florian Grundbacher, Tomasz Kobos

Many classical problems in convex geometry can be cast as optimization problems under certain containment conditions. The arguably best-understood example is volume-maximization of…

math.FA2026

A Complex Analogue of Spencer's Six Standard Deviations Theorem and the Complex Banach-Mazur Distance

Tomasz Kobos, Marin Varivoda

We investigate a complex analogue of Spencer's Six Standard Deviations Theorem. Specifically, we propose the following conjecture: for any dimension , given vectors $a_1,…

math.MG2026

Equilateral dimension of the planar Banach--Mazur compactum

Tomasz Kobos, Konrad Swanepoel

We prove that there are arbitrarily large equilateral sets of planar and symmetric convex bodies in the Banach--Mazur distance. The order of the size of these -equilateral sets…

math.MG2025

On Certain Extremal Banach-Mazur Distances and Ader's Characterization of Distance Ellipsoids

Florian Grundbacher, Tomasz Kobos

A classical consequence of the John Ellipsoid Theorem is the upper bound on the Banach-Mazur distance between the Euclidean ball and any symmetric convex body in $\mathb…