math.GR — Group Theory
The Sharp Commutator Bound for the Polymath14 Inequality
We present a simplified proof of the Polymath14 inequality, along with a new sharpness result.
Browse
math.GT — Geometric Topology
math.GR — Group Theory
We present a simplified proof of the Polymath14 inequality, along with a new sharpness result.
math.GT — Geometric Topology
We prove that the modular torus uniquely minimizes the area of the stable-norm unit ball among complete finite-area hyperbolic once-punctured tori, resolving the McShane--Rivin area conjecture. It therefore has fewer simple closed geodesics of length at most than any fixed nonmodular torus for all sufficiently large . We also bound the area increase away from the modular torus and determine its leading growth and first correction term as the systole tends to zero, with error bounds independent of the twist.