Balancing vectors and convex bodies
Studia Mathematica, Tome 106 (1993) no. 1, pp. 93-100
Voir la notice de l'article provenant de la source Institute of Mathematics Polish Academy of Sciences
Let U, V be two symmetric convex bodies in $ℝ^n$ and |U|, |V| their n-dimensional volumes. It is proved that there exist vectors $u_1,...,u_n ∈ U$ such that, for each choice of signs $ε_1,...,ε_n = ± 1$, one has $ε_1 u_1 + ... + ε_n u_n ∉ rV$ where $r = (2πe^2)^{-1/2} n^{1/2}(|U|/|V|)^{1/n}$. Hence it is deduced that if a metrizable locally convex space is not nuclear, then it contains a null sequence $(u_n)$ such that the series $∑_{n = 1}^∞ ε_n u_{π(n)}$ is divergent for any choice of signs $ε_n = ± 1$ and any permutation π of indices.
Keywords:
balancing vectors, Steinitz constant
Affiliations des auteurs :
Wojciech Banaszczyk 1
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author = {Wojciech Banaszczyk},
title = {Balancing vectors and convex bodies},
journal = {Studia Mathematica},
pages = {93--100},
publisher = {mathdoc},
volume = {106},
number = {1},
year = {1993},
doi = {10.4064/sm-106-1-93-100},
language = {en},
url = {http://geodesic.mathdoc.fr/articles/10.4064/sm-106-1-93-100/}
}
Wojciech Banaszczyk. Balancing vectors and convex bodies. Studia Mathematica, Tome 106 (1993) no. 1, pp. 93-100. doi: 10.4064/sm-106-1-93-100
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