K. Kannaka

activity

20192026

collaborators

5 papers

math.DG2026

Hurwitz-Radon numbers and proper actions of semisimple Lie groups

Kazuki Kannaka, Koichi Tojo

We study proper isometric actions of non-compact semisimple Lie groups on pseudo-Riemannian symmetric spaces. Motivated by Okuda's classification of semisimple symmetric spaces adm…

math.DG2025

Zariski-dense deformations of standard discontinuous groups for pseudo-Riemannian homogeneous spaces

Kazuki Kannaka, Toshiyuki Kobayashi

Let $X = G / H$ be a homogeneous space of a Lie group $G$ . When the isotropy subgroup $H$ is non-compact, a discrete subgroup $Γ$ may fail to act properly discontinuously on $X$ . In th…

math.DG2023

Zariski dense discontinuous surface groups for reductive symmetric spaces

Kazuki Kannaka, Takayuki Okuda, Koichi Tojo

Let $G / H$ be a homogeneous space of reductive type with non-compact $H$ . The study of deformations of discontinuous groups for $G / H$ was initiated by T.~Kobayashi. In this paper, w…

math.SP2020

Linear Independence of Generalized Poincaré Series for Anti-de Sitter 3-Manifolds

Kazuki Kannaka

Let $Γ$ be a discrete group acting properly discontinuously and isometrically on the three-dimensional anti-de Sitter space $AdS^{3}$ , and $□$ the Laplacian which is…

math.GR2019

Counting orbits of certain infinitely generated non-sharp discontinuous groups for the anti-de Sitter space

Kazuki Kannaka

Inspired by an example of Gueritaud-Kassel [Geom. Topol. 2017], we construct a family of infinitely generated discontinuous groups $Γ$ for the 3-dimensional anti-de Sitter space $\…