George Raptis

Publications Students

Conferences Courses

Current Teaching & Activities

Winter Semester 2026/27 (Thessaloniki)

• Lecture course Advanced Topics in Algebra (4th year, in Greek)
[elearning]
• Seminar Introduction to K-theory (Master's degree, in Greek)
[Seminar Schedule]

• HOPEGA Research Seminars (in English, hybrid)

• WORKSHOP Algebra & Geometry Days in Thessaloniki
Thessaloniki, 14-15 December 2026, organised with P. Batakidis and Ch. Psaroudakis

Spring Semester 2027 (Thessaloniki)

• Lecture course Algebraic Structures II (2nd year, in Greek)
[elearning]
• Lecture course Algebraic Topology (Master's degree, in Greek)
[elearning]

• HOPEGA Research Seminars (in English, hybrid)

Thesis Supervision

PhD

• V. Patzalis, PhD thesis, Aristotle University of Thessaloniki, in progress.
• Nikita Müller, PhD thesis, Johannes Gutenberg University Mainz/Aristotle University of Thessaloniki, in progress.
• Fernando Yamauti, PhD thesis, University of Regensburg/University of Sao Paulo, in progress. (co-supervision with H. L. Mariano)

• Johannes Witzig, PhD thesis, University of Regensburg, 2023 (co-supervision with C. Löh)
Title: Universality and Examples in the Context of Functorial Semi-Norms
• Hoang Kim Nguyen, PhD thesis, University of Regensburg, 2018 (supervised jointly with U. Bunke)
Title: Theorems in Higher Category Theory and Applications

• S. Pedretti, Master's thesis, University of Bologna, 2026 (expected), (supervised jointly with M. Moraschini).
• P. Giagtzoglou, Master's thesis, Aristotle University of Thessaloniki, 2026 (expected).
• N. Fachravar, Master's thesis, Aristotle University of Thessaloniki, 2026 (expected).

• S. Lang, Master's thesis, University of Regensburg, 2023. Title: The ∞-topos of spaces and applications.
• T. Wagenpfeil, Master's thesis, University of Regensburg, 2022. Title: Lewis's theorem and model categories of spectra.
• H. Gindi, Master's thesis, University of Regensburg, 2019. Title: Rigidification and the coherent nerve for enriched quasicategories.
• T. Witzig, Master's thesis, University of Regensburg, 2019. Title: The Blakers-Massey theorem: new proofs and generalizations.
• O. Trinkaus, Master's thesis, University of Regensburg, 2019. Title: Configuration spaces in stable homotopy theory.
• M. Mages, Master's thesis, University of Regensburg, 2019. Title: Topological K-theory and the Hopf invariant one problem.
• G. Schwalbe, Master's thesis, University of Regensburg, 2018. Title: Immersions and characteristic classes of manifolds.

• R. Werhahn, Bachelor's thesis, University of Regensburg, 2020. Title: The representability theorems of Brown and Adams.
• T. Wagenpfeil, Bachelor's thesis, University of Regensburg, 2020. Title: Homotopy theory of categories and Quillen's Theorems A and B.

Previous Teaching & Activities (Thessaloniki)

Winter Semester 2025/26 (Thessaloniki)

• Lecture course Elements of Linear Algebra (1st year, in Greek)
[elearning]
• Lecture course Algebraic Topology II (Master's degree, in Greek)
[elearning]

• HOPEGA Research Seminars (in English, hybrid)

• WORKSHOP Algebra & Geometry Day in Thessaloniki
Thessaloniki, 15 December 2025, organised with P. Batakidis and Ch. Psaroudakis

Spring Semester 2026 (Thessaloniki)

Winter Semester 2024/25 (Thessaloniki)

• Lecture course Elements of Linear Algebra (1st year, in Greek)
   [elearning]
• Lecture course Advanced Topics in Algebra (4th year, in Greek)
   [elearning]

• HART Research Seminar on Koszul duality (in English, hybrid)
   with Ch. Psaroudakis. Monday 12-15
• Seminar on Homotopy Type Theory (in English, hybrid)
   with N. Rigas and P. Karazeris [course webpage] Thursday 18-21

Spring Semester 2025 (Thessaloniki)

• Lecture course Algebraic Structures II (2nd year, in Greek)
   [elearning]
• Lecture course Algebraic Topology (Master's degree, in Greek)
   [elearning]

• (ctd.) HART Research Seminar on Koszul duality (in English, hybrid)
   with Ch. Psaroudakis. Monday 12-15
• (ctd.) Seminar on Homotopy Type Theory (in English, hybrid)
   with N. Rigas and P. Karazeris [course webpage] Thursday 18-21

• CONFERENCE: Derived Representation Theory and Triangulated Categories
Thessaloniki, 23-27 June 2025, organised with Ch. Psaroudakis

Previous Teaching & Activities (Regensburg)

Winter Semester 2023/24 (Regensburg)

• Lecture course Acyclic maps and the plus construction
   Fr 12-14, M103. Exercises: Wed 12-14, M103. [GRIPS]
• Seminar Katastrophentheorie/Catastrophe Theory
   Mi 12-14, M103. [cancelled]
• Übung Algebraic Topology III
   Mo 10-12, M104.
• AG Seminar
   Do 12-14, M311.

Summer Semester 2024 (Regensburg)

• Blockseminar Stratifolds and singular (co)homology
   during 4-12 April.
   For more information about the seminar see GRIPS
• Lecture course Cut-and-paste invariants of manifolds
   Mo 8-10, M102. Exercises: Th 8-10, M009.
   For more information about the course see GRIPS
• Seminar K-theory of finite fields (with G. Bertizzolo)
   Th 10-12, PHY 9.1.09.
   For more information about the seminar see here

• CONFERENCE: From Analysis to Homotopy Theory
in honor of Ulrich Bunke's 60th birthday
Greifswald, 13-17 May 2024, organised with B. Ammann, T. Nikolaus, K. Waldorf

Winter Semester 2022/23 (Regensburg)

• On Sabbatical granted by the Academic Research Sabbatical Program of the
   University of Regensburg.
• September 2022: Follow-up Workshop to JTP Topology and Trimester Program
   Spectral Methods in Algebra, Geometry, and Topology, Hausdorff Institute for
   Mathematics, Bonn.

• WORKSHOP: Recent Advances in Bounded Cohomology
Regensburg, 26-30 September 2022, organised with C. Löh and M. Moraschini

Summer Semester 2023 (Regensburg)

• Proseminar Elementargeometrie
   Mo 14-16, M009. [GRIPS]
• Noncommutative Motives Reading Group
   Di 16-18, M311.
• AG Seminar
   Do 12-14, M311.

• WORKSHOP: Algebraic K-theory of spaces
Regensburg, 24-28 July 2023, organised with Ch. Winges

Winter Semester 2021/22 (Regensburg)

• Lineare Algebra II
     Mo 10-12, Di 12-14, H31 + online
     GRIPS
•   Higher Invariants Oberseminar (HIOB): Aspherical Manifolds
     Mo 12-14 (SFB Seminar Room + online) [Seminar Schedule]

Summer Semester 2022 (Regensburg)

• Seminar Homotopical Algebra - Model Categories
[Seminar Schedule] Wed. 16-18 (H31/online). More details in GRIPS

• Seminar Morse Theory [Seminar Schedule]
Fri. 10-12 (M102/online). More details in GRIPS

Winter Semester 2020/21 (Regensburg)

• Lineare Algebra II
     Mo 10-12, Di 12-14 (online)
• Bachelorseminar
     Do 14-16 GRIPS
• Higher Invariants Oberseminar (HIOB)
     Mo 12-14 (online)

Summer Semester 2021 (Regensburg)

• Seminar Topics in Homotopy Theory [Seminar Schedule]
   Wed. 16-18 (online). Registration for the Seminar via GRIPS
• Examenskurs Algebra und Zahlentheorie LGy
   Mo 10-12, Mi 12-14 (online). Registration via GRIPS
• Higher Invariants Oberseminar (HIOB)
   Mo 12-14 (online)

Winter Semester 2019/20 (Regensburg)

• Übung Algebraische Topologie I
Fri. 8-10, M 009
• Seminar Topics in Higher Category Theory
Tue. 16-18, M101

Summer Semester 2020 (Regensburg)

• Seminar Katastrophentheorie/Catastrophe Theory
Mi 16-18 (online)
• HIOB Seminar (postponed)
• Examenskurs Algebra und Zahlentheorie LGy
Link to GRIPS

Winter Semester 2018/19 (Regensburg)

• On Sabbatical granted by the Academic Research Sabbatical Program of the University of
Regensburg.
• September-December 2018: Scientific Programme Homotopy harnessing higher structures,
Isaac Newton Institute for Mathematical Sciences, Cambridge.
• February 2019: Academic Visitor, Mathematical Institute, University of Oxford.

Summer Semester 2019 (Regensburg)

• Seminar Simple homotopy theory and Whitehead groups
[Seminar Schedule]

• WORKSHOP: Derivators, Regensburg, 9-12 April, 2019, organised with D.-C. Cisinski