Talks



    Talks at Conferences and Workshops

  1. XIII. Forum of Partial Differential Equations 06/2024
    Plenary Talk, Bedlewo
    Talk: ``Bifurcation for a Class of Indefinite Elliptic Systems\\ by Comparison Theory for the Spectral Flow''

  2. AIMS Conference on Dynamical Systems, Differential Equations and Applications 05/2023
    Session: Geometric methods in spectral theory of travelling waves, Wilmington
    Talk: ``K-theoretic Methods in the Computation of the Maslov Index''

  3. Conference on Mathematics of Wave Phenomena 02/2022
    Session: Geometric Methods in Spectral Theory of Travelling Waves, Karlsruhe
    Talk: ``The G-equivariant Spectral Flow and Bifurcation''

  4. Annual Meeting of the German Mathematical Society (DMV) 09/2020
    Session: Geometric Analysis and Applications, Chemnitz
    Talk: ``On the Fredholm Lagrangian Grassmannian, Spectral Flow and ODEs in Hilbert Spaces''

  5. Joint Meeting of the Italian Mathematical Society (UMI) and the Polish Mathematical Society (PTM) 09/2018 Session 21: New Perspectives in Singular Hamiltonian Systems, Wroclaw
    Talk: ``On the Fredholm Lagrangian Grassmannian, Spectral Flow and ODEs in Hilbert Spaces''

  6. Interfaces between Geometric Analysis and Mathematical Physics II 05/2018
    Institut Mittag-Leffler, Djursholm Talk: ''On the Fredholm Lagrangian Grassmannian, Spectral Flow and ODEs in Hilbert Spaces''

  7. Index Theorems in Analysis, Geometry and Mathematical Physics 05/2017 University of Kent, Canterbury
    Talk: ''Spectral Flow and Bifurcation''

  8. Interfaces between Geometric Analysis and Mathematical Physics 07/2016
    Institut Mittag-Leffler, Djursholm
    Talk: ``Spectral Flow and Bifurcation''

  9. Annual Meeting of the German Mathematical Society (DMV) 09/2015
    Section 3: Differential Equations and Applications, Hamburg
    Talk: ``On bifurcation for semilinear elliptic Dirichlet problems on shrinking domains''

  10. International Conference on Nonlinear Operators Differential Equations and Applications 07/2015
    Section on Variational Methods, Cluj-Napoca
    Talk: ``The Spectral Flow in Variational Bifurcation Theory''

  11. Conference: Complex Patterns in Nonlinear Phenomena 01/2015
    with a day dedicated to the 70. birthday of J. Pejsachowicz, Torino
    Talk: ``Spectral flow, crossing forms and homoclinics of Hamiltonian systems''

  12. Joint Meeting of the German Mathematical Society (DMV) and the Polish Mathematical Society (PTM) 09/2014
    Session 38: Variational Methods in Nonlinear Analysis, Poznan
    Talk: ``A family index theorem for Hamiltonian systems and bifurcation''

  13. Workshop: Elliptic and Parabolic Equations 09/2013
    RTG 1463: Analysis, Geometry and String Theory, Hannover
    Talk: ``On bifurcation for semilinear elliptic Dirichlet problems and the Morse-Smale index theorem''

  14. Conference: Topology and Nonlinear Problems 08/2013
    Dedicated to the 80. birthday of K. Gemba, Banach Center, Warsaw
    Talk: ``A family index theorem for Hamiltonian systems and bifurcation''

  15. Conference: Variational and Topological Methods in Nonlinear Phenomena 06/2013
    Dedicated to the 70. birthday of A. M. Micheletti and G. Palmieri, Alghero
    Talk: ``A family index theorem for Hamiltonian systems and bifurcation''

  16. Workshop: Indice di Maslov per operatori differenziali in dimensione finita ed infinita II 06/2013
    Universit\`a degli Studi di Firenze, Florence
    Talk: ``On the Morse index theorem in semi-Riemannian geometry''

  17. Workshop: Indice di Maslov per operatori differenziali in dimensione finita ed infinita I 02/2013
    Universit\`a degli Studi di Torino, Turin
    Talk: ``On bifurcation for semilinear elliptic Dirichlet problems and the Morse-Smale index theorem''

  18. Workshop: Analysis and Geometric Singularities 05/2012
    MFO Oberwolfach
    Talk: ``On the Index Bundle for Families of Unbounded Operators''

  19. Workshop: Topological and Variational Methods in Differential Equations 04/2012
    Politecnico di Torino
    Talk: ''A Family Index Theorem for periodic Hamiltonian Systems''

  20. Workshop: Index Theory, nonlinear Dirac Equations and Morse-Floer Homology03/2009
    Politecnico di Torino
    Talk: ``On the Spectral Flow for Gap Continuous Paths of Selfadjoint Fredholm Operators''

  21. Workshop: Young Topologists and New Topology 08/2006
    Banach Mathematical Center Bedlewo
    Talk: ``A Morse index theorem for perturbed geodesics on Semi-Riemannian manifolds''


    22. Talks at Research Seminars

  22. Analysis Seminar 06/2023
    Technical University of Freiberg, Freiberg
    Talk: ``The Equivariant Spectral Flow and Bifurcation"

  23. The Dutch Differential Topology and Geometry Seminar 04/2023
    Vrije Universiteit Amsterdam
    Talk: ``Spaces of Unbounded Operators and the Spectral Flow"

  24. N-Cities Seminar 07/2022
    TU Chemnitz
    Talk: ``The Equivariant Spectral Flow and Bifurcation for functionals with Symmetries"

  25. Nonlinear Differential Equations Seminar 12/2021
    University of Toru\'n, Torun
    Talk: ``The Equivariant Spectral Flow and Bifurcation for Hamiltonian Systems with Symmetries"

  26. Analysis Seminar 05/2021
    University of Gießen, Gießen
    Talk: ``The Equivariant Spectral Flow and Bifurcation for Hamiltonian Systems with Symmetries"

  27. Analysis Seminar 11/2019
    University of Leipzig, Leipzig
    Talk: ``On the Fredholm Lagrangian Grassmannian, Spectral Flow and ODEs in Hilbert Spaces''

  28. Analysis Seminar 07/2019
    Technical University of Dresden, Dresden
    Talk: ``On the Fredholm Lagrangian Grassmannian, Spectral Flow and ODEs in Hilbert Spaces''

  29. Analysis Seminar 06/2019
    University of Bochum, Bochum
    Talk: ``On the Fredholm Lagrangian Grassmannian, Spectral Flow and ODEs in Hilbert Spaces''

  30. Nonlinear Analysis Seminar 11/2017
    Politechnika Gda\'nska, Gdansk
    Talk: ``On the Fredholm Lagrangian Grassmannian and the Spectral Flow''

  31. Nonlinear Analysis Seminar 10/2017
    University of Toru\'n, Torun
    Talk: ``On the Fredholm Lagrangian Grassmannian and the Spectral Flow''

  32. Analysis Seminar 11/2016
    University of Kent, Canterbury
    Talk: ``Shrinking Domains and Bifurcation''

  33. Analysis Seminar 02/2016
    University of Kent, Canterbury
    Talk: ``Spectral Flow - Definition, Properties and Applications''

  34. Nonlinear Analysis Seminar 11/2015
    Politechnika Gda\'nska, Gdansk
    Talk: ``On the Spectral Flow in Variational Bifurcation Theory''

  35. Analysis Seminar 11/2015
    University of Kent, Canterbury
    Talk: ``On the Spectral Flow in Variational Bifurcation Theory''

  36. Oberseminar Globale Analysis 07/2015
    Hausdorff Center for Mathematics, Bonn
    Talk: ``Spectral flow, crossing forms and homoclinics of Hamiltonian systems''

  37. Oberseminar Analysis 01/2015
    Universit\"at Potsdam, Potsdam
    Talk: ``An introduction to the spectral flow''

  38. Oberseminar Dynamische Systeme 10/2014
    Ruhr Universit\"at Bochum, Bochum
    Talk: ``Spectral flow, crossing forms and homoclinics of Hamiltonian systems''

  39. Forschungsseminar Geometrische Analysis 02/2014
    Humboldt-Universit\"at zu Berlin, Berlin
    Talk: ``Crossing forms, bifurcation and the Morse index''

  40. Nonlinear Analysis Seminar 11/2013
    Politechnika Gda\'nska, Gdansk
    Talk: ``On the existence of non-trivial harmonic spinors''

  41. Forschungsseminar Geometrische Analysis 11/2013
    Humboldt-Universit\"at zu Berlin, Berlin
    Talk: ``A family index theorem for Hamiltonian systems''

  42. Oberseminar Analysis and Theoretische Physik 05/2013
    Leibniz Universit\"at Hannover, Hanover
    Talk: ``A family index theorem for Hamiltonian systems and bifurcation''

  43. Nonlinear Analysis Seminar 11/2012
    Universit\`a degli Studi di Milano-Bicocca, Milan
    Talk: ``Bifurcation results for critical points of families of functionals''

  44. Nonlinear Analysis Seminar 11/2012
    Universit\`a degli Studi di Torino, Turin
    Talk: ``Bifurcation results for critical points of families of functionals''

  45. Geometry Seminar 06/2012
    Universit\`a del Salento, Lecce
    Talk: ``A family index theorem for second order ODE and geodesics in semi-Riemannian manifolds''

  46. Oberseminar Differentialgeometrie 11/2010
    Universit\"at Augsburg, Augsburg
    Talk: ``On the Morse Index Theorem in semi-Riemannian Geometry''

  47. Oberseminar Geometrie und Topologie 01/2009
    Georg-August Universit\"at G\"ottingen, G\"ottingen
    Talk: ``On the Spectral Flow for Gap Continuous Paths of Selfadjoint Fredholm Operators''


    48. Other Talks

  48. Lange Nacht der Wissenschaften 11/2021
    TU Clausthal
    Talk: ``1,2,3...'ne Menge! Wie viel ist Unendlich?''

  49. Mathematisches Kolloquium 05/2021
    Universit\"at G\"ottingen
    Talk: ``The Spectral Flow and Bifurcation''

  50. Seminar for Young Mathematicians 05/2021
    Politechnika Gda\'nska, Gdansk
    Talk: ``The Spectral Flow and Bifurcation''

  51. Lange Nacht der Wissenschaften 07/2019
    Universit\"at Halle
    Talk: ``1,2,3...'ne Menge! Wie viel ist Unendlich?

  52. Mathematisches Kolloquium 10/2018
    Universit\"at Erlangen
    Talk: ``The Spectral Flow and Bifurcation''

  53. Mathematisches Kolloquium 12/2016
    Universit\"at Potsdam
    Talk: ``The Buckling of the Euler Rod''

  54. Littoral-Kent Seminar 05/2016
    Joint biannual Colloquium with Universit\'e du Littoral
    University of Kent, Canterbury
    Talk: ``$K$-theoretic Methods in the Bifurcation Theory of Discrete Dynamical Systems''

  55. Meeting of the SFB 647 ``Space--Time--Matter'' 07/2015
    Hotel Bollmannsruh, P\"awesin
    Talk: ``The Index Bundle and Higher Spectral Flow''

  56. Bridges between Mathematics and its Applications 11/2014
    Technical University of Berlin, Berlin
    Talk: ''The spectral flow in variational bifurcation theory''

  57. Colloqui Matematici 10/2014
    Universit\`a degli studi di Bari, Bari
    Talk: ''The spectral flow in variational bifurcation theory''

  58. Mathematisches Kolloquium 12/2013
    Heinrich Heine Universit\"at D\"usseldorf, D\"usseldorf
    Talk: ``On the Index Bundle for Families of Unbounded Operators''

  59. Meeting of the SFB 647 12/2013
    \textbf{``Space--Time--Matter''}
    Akademie Berlin--Schm\"ockwitz, Schm\"ockwitz
    Talk: ``The index bundle, spectral flow and geometric operators''

  60. Webinar: Maslov index, spectral flow and stability 01/2013
    Organised by C. Jones, University of North Carolina at Chapel Hill
    Talk: ``A family index theorem for Hamiltonian systems''

  61. Webinar: Maslov index, spectral flow and stability 12/2012
    Organised by C. Jones, University of North Carolina at Chapel Hill
    Talk: ``On the Morse index theorem in semi-Riemannian geometry''

  62. Meeting of the Research Training Group 06/2011
    ``Mathematical Structures in Modern Quantum Physics''
    Haus Hessenkopf, Goslar
    Talk: ``On the Index Bundle for Families of Unbounded Operators''

  63. Students' Conference (annual meeting of DMV) 09/2008
    University of Erlangen-N\"urnberg
    Talk: ``Der Spektralindex perturbierter semi-Riemannscher Geod\"aten als Windungszahl''