Tomasz Kobos

activity

20152025

collaborators

4 papers

math.FA2025

Spaces with the maximal projection constant revisited

Tomasz Kobos

Let $n \geq 2$ be an integer such that an equiangular set of vectors $w_{1}, \dots, w_{d}$ of the maximal possible cardinality (that is, attaining the classical Gerzon upper bound) ex…

math.FA2025

$2$ -strong uniqueness of a best approximation and of minimal projections in complex polytope norms and their duals

Tomasz Kobos, Grzegorz Lewicki

We study a property of $2$ -strong uniqueness of a best approximation in a class of finite-dimensional complex normed spaces, for which the unit ball is an absolutely convex hull of…

math.FA2022

On the dimension of the set of minimal projections

Tomasz Kobos, Grzegorz Lewicki

Let $X$ be a finite-dimensional normed space and let $Y \subseteq X$ be its proper linear subspace. The set of all minimal projections from $X$ to $Y$ is a convex subset of the spa…

math.FA2015

A uniform estimate of the relative projection constant

Tomasz Kobos

The main goal of the paper is to provide a quantitative lower bound greater than $1$ for the relative projection constant $λ (Y, X)$ , where $X$ is a subspace of $ℓ_{2 p}^{m}$ space…

Spaces with the maximal projection constant revisited

2-strong uniqueness of a best approximation and of minimal projections in complex polytope norms and their duals

On the dimension of the set of minimal projections

A uniform estimate of the relative projection constant

$2$ -strong uniqueness of a best approximation and of minimal projections in complex polytope norms and their duals