Jonas Beyrer


About me:

I am currently a postdoc at the University of Bonn in the group of Ursula Hamenstädt.

I recieved my PhD in September 2018 under the supervision of Viktor Schroeder at the Univeristy of Zürich. After that I was a postdoc at the university of Heidelberg in the group of A. Wienhard and B. Pozzetti (supported by the SPP2026) and at the IHES in the group of Fanny Kassel (supported by the SNF).

Email: jbeyrer@uni-bonn.de

Research interests:

I am interested in negatively and non-positively curved groups and spaces, with a focus on boundaries and asymptotic behavior.

Currently I am working a lot with discrete subgroups of Lie groups, mostly Anosov representations and higher rank Teichmüller theory. I am also very interested in CAT(0) cube complexes and hyperbolic groups.

Publications and Preprints:

  1. Positive surface group representations in PO(p,q), with B. Pozzetti

arXiv:2106.14725

  1. Degenerations of k-positive surface group representations, with B. Pozzetti

arXiv:2106.05983

  1. A collar lemma for partially hyperconvex surface group representations, with B. Pozzetti

Transactions of the AMS 374 (2021), 6927 - 6961 (pdf, arXiv)

  1. Cross ratios on CAT(0) cube complexes and marked length-spectrum rigidity, with E. Fioravanti

Journal of the LMS (pdf, arXiv)

  1. Cubulations and cross ratios on contracting boundaries, with E. Fioravanti

Mathematische Annalen (to appear, arXiv)

  1. CAT(0) cube complexes are determined by their boundary cross ratio, with E. Fioravanti and M. Incerti-Medici

Groups, Geometry and Dynamics 15 (2021), 313 - 333 (pdf)

  1. Cross ratios on boundaries of symmetric spaces and Euclidean buildings,

Transformation Groups 26(1) (2021), 31–68 (pdf)

  1. Trees and ultrametric Möbius structures, with V. Schroeder

V. P-Adic Num. Ultrametr. Anal. Appl. 9 (2017), 247-256 (pdf)

  1. A complete description of the antipodal set of most symmetric spaces of compact type,

Osaka J. Math 55(3) (2018), 567-586 (pdf)


Other works

  1. Marked length spectrum rigidity for actions on CAT(0) cube complexes,

Oberwolfach reports (Differentialgeometrie im Großen) 16(2) (2019) 1791–1839 (pdf)