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20172026
most citedExtremal Banach-Mazur distance between a symmetric convex body and an arbitrary convex body on the plane

3 citations · 3 across the 9 of their papers we have counts for

collaborators

10 papers

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.MG2025

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.MG2024

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…

math.MG2023

On the Banach-Mazur Distance in Small Dimensions

Tomasz Kobos, Marin Varivoda

We establish some results on the Banach-Mazur distance in small dimensions. Specifically, we determine the Banach-Mazur distance between the cube and its dual (the cross-polytope)…

math.FA2022

On non-linear mappings preserving the semi-inner product

Tomasz Kobos, Paweł Wójcik

We say that a smooth normed space has a property (SL), if every mapping preserving the semi-inner product on is linear. It is well known that every Hilbert spac…

math.FA2020

A uniform lower bound on the norms of hyperplane projections of spherical polytopes

Tomasz Kobos

Let be a centrally symmetric spherical and simplicial polytope, whose vertices form a net in the unit sphere in . We prove a uniform lower bound on…

math.FA2017★ 3 cited

Extremal Banach-Mazur distance between a symmetric convex body and an arbitrary convex body on the plane

Tomasz Kobos

We prove that if are convex bodies such that is symmetric and the Banach-Mazur distance between and is equal to , then is a triangle.

math.FA2017

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…