A note on the Steinitz Lemma
Gergely Ambrus, Rainie Heck
TL;DR
This note refines the Euclidean Steinitz problem by introducing the $\varepsilon$-Steinitz constant $S_\varepsilon(B_2^d)$ and showing that $S(B_2^d) \le \frac{1}{\varepsilon}\left(S_\varepsilon(B_2^d)+200\sqrt{\frac{d}{\log d}}\right)$ for all $0<\varepsilon<1$ and $d\ge 2$. The approach reduces the unrestricted problem to a restricted version involving vectors with nearly unit norm, via a constructive partition into cone-contained blocks and a bound on spherical-cap measures using $t=\sqrt{\frac{\log d}{2d}}$. Central to the argument are three technical lemmas that bound the sums of long and short vectors and control the spherical-cap measure $\sigma_t$, which together yield an additive error of order $O\big(\sqrt{d/\log d}\big)$. Consequently, progress on the restricted nearly-unit problem with such an additive term would translate into progress on the original problem, potentially achieving an $O(\sqrt{d})$ bound for the Euclidean Steinitz constant. The work connects geometric probability with vector-sum combinatorics through a structured partition and transference via the $\varepsilon$-Steinitz framework.
Abstract
We prove that the Euclidean Steinitz problem may be reduced to its restriction to ``nearly unit'' vectors at the cost of an additive $O\Big(\sqrt{\frac{d}{\log d}}\Big)$ error.
