Uniform spectral gap of scl in $2$-orbifolds
Geometric Topology
2026-05-28 v2 Group Theory
Abstract
We show a uniform spectral gap of stable commutator length for all compact hyperbolic -orbifolds relative to the peripheral subgroups. Except for the case of a sphere with three cone points, we have an explicit uniform gap . These estimates are needed in understanding stable commutator length in -manifolds. Our methods use explicit quasimorphisms for the generic case, and use hyperbolic geometry (pleated surfaces) for the exceptional case of a sphere with three cone points.
Keywords
Cite
@article{arxiv.2604.21059,
title = {Uniform spectral gap of scl in $2$-orbifolds},
author = {Lvzhou Chen and Nicolaus Heuer},
journal= {arXiv preprint arXiv:2604.21059},
year = {2026}
}
Comments
v2: minor revision, added acknowledgment; 20 pages, 4 figures. This is separated from the authors' earlier paper arXiv:1910.14146, which was shortened for publication purposes