The full asymptotic expansion of analytic torsion on homogeneous spaces
Kai Köhler
TL;DR
This work provides explicit full asymptotic expansions for the equivariant complex analytic torsion $T_t(G/K,L^{\ell})$ on compact complex homogeneous spaces as $\ell\to\infty$, expressed via Lerch zeta data and representation-theoretic inputs. It treats both isolated fixed points and Hermitian-symmetric cases, and extends to torsion forms in fibrations, with rigorous error bounds. The expansions are checked against classical BV and Fi results and applied to lattice representations of Chevalley groups and to the Jantzen sum formula, yielding computable arithmetic data. The framework advances Arakelov geometry by providing precise coefficient formulas for torsion-related invariants.
Abstract
The full asymptotic expansion of the equivariant complex Ray-Singer torsion for high powers of line bundles on symmetric spaces is given in an explicit form. In the case of isolated fixed points this expansion is given for general complex homogeneous spaces. Furthermore the full asymptotic expansion is given for the complex analytic torsion form associated to fibrations by projective curves. The expansions are compared with results by Bismut-Vasserot, Finski and Puchol. The results are applied to lattice representations of Chevalley groups.
