Philipp Reiser

Welcome to my homepage! While I do not currently hold an academic position, I am still active in mathematical research. I was a postdoc at the Department of Mathematics of the University of Fribourg in the group of Anand Dessai from September 2022 to August 2025. I received my PhD in 2022 at the Karlsruhe Institute of Technology (KIT) under the supervision of Wilderich Tuschmann and Fernando Galaz-García. My thesis can be found here.

My research interests lie within Riemannian geometry and geometric topology. Topics I have worked on include the following:

  • Topology and geometry of Riemannian manifolds of positive Ricci curvature
  • Various other notions of lower curvature bounds (sectional, scalar, intermediate Ricci curvature)
  • Surgery constructions with or without a lower curvature bound
  • Generalised notions of Ricci curvature
  • Spaces and moduli spaces of Riemannian metrics
  • Torus actions and Lie group actions with low-dimensional orbit space

You can find two online talks I gave here and here.

For more information, see my CV.

Philipp Reiser

✉ philipp.reiser.math@mailbox.org
ORCID iD icon 0000-0002-7997-7484

Preprints

  1. Ricci curvature and minimal hypersurfaces with large Betti numbers, with Davi Maximo and Daniele Semola, 2025 (arXiv).
  2. Surgery and positive Bakry-Émery Ricci curvature, with Francesca Tripaldi, 2024 (arXiv).
  3. Positive Ricci curvature on connected sums of fibre bundles, 2024 (arXiv).
  4. A generalization of the Perelman gluing theorem and applications, with David Wraith, 2023 (arXiv).

Publications

  1. Positive intermediate Ricci curvature on connected sums, with David Wraith. Algebr. Geom. Topol., 2025 (doi, arXiv).
  2. Positive intermediate Ricci curvature on fibre bundles, with David Wraith. SIGMA Symmetry Integrability Geom. Methods Appl., 2025 (doi, arXiv).
  3. Free torus actions and twisted suspensions, with Fernando Galaz-García. Forum Math. Sigma, 2025 (doi, arXiv).
  4. Examples of tangent cones of non-collapsed Ricci limit spaces. Nonlinear Anal., 2025 (doi, arXiv).
  5. Metrics of Positive Ricci Curvature on Simply-Connected Manifolds of Dimension 6k. J. Topol., 2024 (doi, arXiv).
  6. Positive Ricci Curvature on Twisted Suspensions. Int. Math. Res. Not. IMRN, 2024 (doi, arXiv).
  7. Intermediate Ricci curvatures and Gromov’s Betti number bound, with David Wraith. J. Geom. Anal., 2023 (doi, arXiv).
  8. Generalized Surgery on Riemannian Manifolds of Positive Ricci Curvature. Trans. Amer. Math. Soc., 2023 (doi, arXiv).
  9. Cohomogeneity One Manifolds and Homogeneous Spaces of Positive Scalar Curvature, with Georg Frenck and Fernando Galaz-García. Bull. Lond. Math. Soc., 2022 (doi, arXiv).
  10. Moduli Spaces of Metrics of Positive Scalar Curvature on Topological Spherical Space Forms. Canad. Math. Bull., 2020 (doi, arXiv).