Photo by Petra Lein (Oberwolfach Archives)

Benjamin Delarue

Name until January 2022: Benjamin Küster

Postdoctoral researcher in mathematics

Member of the Spectral analysis group in the Institute of Mathematics at Paderborn University, Germany

Principal Investigator of the project Resonances for non-compact locally symmetric spaces in the SPP 2026 Geometry at Infinity of the DFG (Deutsche Forschungsgemeinschaft)

Contact details available here

My profiles on Google scholar and ResearchGate

Research interests


  1. Locally homogeneous Axiom A flows I: projective Anosov subgroups and exponential mixing (with Daniel Monclair and Andrew Sanders)
    arXiv Preprint (2024)
  2. Quantum resonances and scattering poles of classical rank one locally symmetric spaces (with Joachim Hilgert)
    arXiv Preprint (2024)
  3. Singular cohomology of symplectic quotients by circle actions and Kirwan surjectivity (with Maximilian Schmitt and Pablo Ramacher)
    arXiv Preprint (2023)
  4. A Riemann-Roch formula for singular reductions by circle actions (with Louis Ioos and Pablo Ramacher)
    arXiv Preprint (2023)
  5. Resonances and weighted zeta functions for obstacle scattering via smooth models (with Philipp Schütte and Tobias Weich)
    Ann. Henri Poincaré 25 (2024), 1607–1656
  6. The Ruelle zeta function at zero for nearly hyperbolic 3-manifolds (with Mihajlo Cekić, Semyon Dyatlov, and Gabriel Paternain)
    Invent. Math. 229 (2022), 303–394
  7. Asymptotic expansion of generalized Witten integrals for Hamiltonian circle actions (with Pablo Ramacher)
    J. Symplectic Geom. 19 (2021), no. 6, 1281–1337
  8. Spectral Theory of the Frame Flow on Hyperbolic 3-Manifolds (with Colin Guillarmou and Charles Hadfield)
    Ann. Henri Poincaré 22 (2021), 3565–3617
  9. Pollicott-Ruelle resonant states and Betti numbers (with Tobias Weich)
    Commun. Math. Phys. 378 (2020), 917–941
  10. Quantum-Classical Correspondence on Associated Vector Bundles Over Locally Symmetric Spaces (with Tobias Weich)
    Int. Math. Res. Not. 2021 (2019), no. 11, 8225–8296
  11. On the semiclassical functional calculus for h-dependent functions
    Ann. Glob. Anal. Geom. 52 (2017), no. 1, 57–97
  12. Quantum ergodicity and symmetry reduction (with Pablo Ramacher)
    J. Funct. Anal. 273 (2017), no. 1, 41-124
  13. Discontinuity of the Fuglede-Kadison determinant on a group von Neumann algebra
    Commun. Math. 22 (2014), no. 2, 141-149


Geometrie für Lehramtsstudierende (Geometry for students of Education), Paderborn University, 2024

Analysis für Informatiker (Analysis for computer scientists), Paderborn University, 2021/22

Symplektische Geometrie und Hamiltonsche Dynamik (Symplectic geometry and Hamiltonian dynamics), Paderborn University, 2017/18

SPP 2026 Geometry at Infinity

My project

SPP 2026 homepage

Selected talks

Brief introduction to Anosov representations, Study group on Patterson-Sullivan Theory, Paderborn 2024

The Ruelle zeta function at zero for nearly hyperbolic 3-manifolds, Online seminar organized by Colin Guillarmou, Nguyen Viet Dang, Frederic Naud, and Gabriel Rivière, January 2021

The frame flow on hyperbolic 3-manifolds, 56th Seminar Sophus Lie, Paderborn, February 2020

Quantum-classical correspondence for resonances on vector bundles, Séminaire Problèmes Spectraux en Physique Mathématique, Institut Henri Poincaré, Paris, January 2019



Selected memories from conferences and workshops

A documentation of the harsh working conditions of a mathematician