English

Growth of quadratic forms under Anosov subgroups

Group Theory 2021-10-04 v2 Differential Geometry Geometric Topology

Abstract

Let ρ:ΓPSLd(K)\rho:\Gamma\rightarrow PSL_d(\mathbb{K}) be a Zariski dense Borel-Anosov representation, for K\mathbb{K} equal to R\mathbb{R} or C\mathbb{C}. Let oo be a form of signature (p,dp)(p,d-p) on Kd\mathbb{K}^d (where 0<p<d)0<p<d). Let So\mathsf{S}^o be the corresponding geodesic copy of the Riemannian symmetric space of PSO(o)PSO(o), inside the Riemannian symmetric space of PSLd(K)PSL_d(\mathbb{K}). For certain choices of oo and every tt large enough, we show exponential bounds for the number of γΓ\gamma\in\Gamma for which the distance between So\mathsf{S}^o and ργSo\rho\gamma\cdot\mathsf{S}^o is smaller than tt. Under an extra assumption, satisfied for instance when the boundary of Γ\Gamma is connected, we show an asymptotic as tt\rightarrow\infty for the counting function relative to a functional in the interior of the dual limit cone.

Keywords

Cite

@article{arxiv.2004.05903,
  title  = {Growth of quadratic forms under Anosov subgroups},
  author = {León Carvajales},
  journal= {arXiv preprint arXiv:2004.05903},
  year   = {2021}
}

Comments

Final version to appear in International Mathematics Research Notices. We now treat the complex case. 50 pages, 6 figures. Comments welcome