Jakob Stoye

Jakob Stoye

Postal address:
Institute for Numerical Analysis
Universitätsplatz 2
D-38106 Braunschweig

Contact:
Room F508, 5th floor of the Forumsgebäude
Phone: +49 531 391 7539
E-Mail: jakob.stoye(at)tu-braunschweig.de

Office hours: by appointment

Research interests:

Numerical Linear Algebra and Matrix Analysis, in particular

  • Matrix manifolds (Stiefel manifold)
  • Nonlinear matrix equations
  • Riemannian optimization

Publications:

  • Zimmermann, R., Stoye, J.: The Injectivity Radius of the Compact Stiefel Manifold under the Euclidean Metric. SIAM Journal on Matrix Analysis and Applications 46(1), 298–309 (2025) (https://doi.org/10.1137/24M1663818)
  • Zimmermann, R., Stoye, J.: High Curvature Means Low Rank: On the Sectional Curvature of Grassmann and Stiefel Manifolds and the Underlying Matrix Trace Inequalities. SIAM Journal on Matrix Analysis and Applications 46(1), 748–779 (2025) (https://doi.org/10.1137/24M1655755)

Participation in Conferences and Presentations:

  • GAMM Annual Meeting 2024, Magdeburg, March 18-22, 2025,
    Presentation "On the injectivity radius of the Stiefel manifold"
  • GAMM Workshop on Applied and Numerical Linear Algebra 2024, Göttingen, September 23-24, 2024,
    Presentation "Injectivity Radius and Curvature Bounds on the Stiefel Manifold​​​​​​​"
  • Nordic Numerical Linear Algebra Meeting 2025, Uppsala, August 19-20, 2025,
    Presentation "Injectivity radius of the Stiefel manifold under the family of β-metrics​​​​​​​"

Teaching at TU Braunschweig:

Summer term 2025

  • Teaching assistant Introduction to Numerical Analysis (Prof. Dr. H. Faßbender)

Winter term 2024/2025

  • Teaching assistant Introduction to Numerical Analysis for computer science (Prof. Dr. H. Faßbender)
  • Lecture and tutorial (in english) of the numerical part of the Ramp up Course Mathematics (teaching appointment)

Summer term 2024

  • Teaching assistant Computer Lab Numerical Analysis (Prof. Dr. M. Bollhöfer)

Winter term 2023/2024

  • Teaching assistant Introduction to Numerical Analysis (Prof. Dr. M. Bollhöfer)
  • Teaching assistant (in english) of the numerical part of the Ramp up Course Mathematics (Prof. Dr. M. Bollhöfer)

Earlier work as student assistant:

  • Tutorials in Linear Algebra 1 (Winter term 19/20)
  • Tutorials in Linear Algebra 2 (Summer term 20)
  • Tutorials in Introduction to Numerical Analysis (Winter term 20/21)
  • Tutorials in Analysis 2 (Summer term 21)
  • Tutorials in Computer-oriented Mathematics 1 and Linear Algebra for Computer Scientists (Winter term 22/23)
  • Preparatory course in Mathematics (2019-2022)