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arXiv · 2608.17660

An improved lower bound for Bloch's constant

Frank Wikström
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Abstract

Let $B$ denote Bloch's constant. We prove \[ B \ge \frac{\sqrt{3}}{4}+0.0153 = 0.448312701\ldots, \] improving the lower bounds by Chen--Gauthier ($\sqrt{3}/4+2\cdot10^{-4}$) and Xiong ($\sqrt{3}/4+3\cdot10^{-4}$). The proof refines Bonk's method through computer-assisted estimates rigorously verified using interval arithmetic.

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Frank Wikström. 2026-08-18. An improved lower bound for Bloch's constant. https://arxiv.org/abs/2608.17660

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