About me

I am universitair docent (assistant professor) in the Department of Mathematics at Radboud University Nijmegen.

My primary area of research is algebraic topology, or more specifically homotopy theory. I am also interested in questions about algebraic K-theory, higher category theory, derived algebraic geometry, and homological algebra.


email address
Phone: +31 24 365 2296

HG03.735, Huygensgebouw, Heyendaalseweg 135, 6525 AJ Nijmegen

Postal address
Steffen Sagave, Radboud Universiteit, IMAPP - Mathematics, PO Box 9010, 6500 GL Nijmegen, The Netherlands


Past activities


  • Spring semester 2019/20
  • Autumn semester 2019/20
    Teaching in previous terms


    1. Homotopical and operator algebraic twisted K-theory
      (joint with Fabian Hebestreit)
      arXiv:1904.01872, pdf-file
    2. Multiplicative parametrized homotopy theory via symmetric spectra in retractive spaces
      (joint with Fabian Hebestreit and Christian Schlichtkrull)
      arXiv:1904.01824, pdf-file
    3. A strictly commutative model for the cochain algebra of a space
      (joint with Birgit Richter)
      arXiv:1801.01060, pdf-file


    (in reverse chronological order of acceptance)

    1. Homotopy invariance of convolution products
      (joint with Stefan Schwede)
      Accepted for publication in International Mathematics Research Notices
      arXiv:1907.05188, pdf-file
    2. Comparing cyclotomic structures on different models for topological Hochschild homology
      (joint with Emanuele Dotto, Cary Malkiewich, Irakli Patchkoria and Calvin Woo)
      Journal of Topology, 12 (2019), no. 4, 1146–1173
      arXiv:1707.07862, pdf-file, published article (open access)
    3. Virtual vector bundles and graded Thom spectra
      (joint with Christian Schlichtkrull)
      Mathematische Zeitschrift 292 (2019), no. 3–4, 975–1016
      arXiv:1410.4492, pdf-file, published article
    4. Generalized Thom spectra and their topological Hochschild homology
      (joint with Samik Basu and Christian Schlichtkrull)
      Journal of the Institute of Mathematics of Jussieu (2017), 1-44, doi:10.1017/S1474748017000421
      arXiv:1608.08388, pdf-file, published article
    5. Presentably symmetric monoidal infinity-categories are represented by symmetric monoidal model categories
      (joint with Thomas Nikolaus)
      Algebraic & Geometric Topology, 17 (2017), 3189–3212.
      arXiv:1506.01475, pdf-file, published article
    6. Logarithmic topological Hochschild homology of topological K-theory spectra
      (joint with John Rognes and Christian Schlichtkrull)
      Journal of the European Mathematical Society (JEMS), 20 (2018), no. 2, 489–527.
      arXiv:1410.2170, pdf-file, published article
    7. Topological Hochschild homology and the cyclic bar construction in symmetric spectra
      (joint with Irakli Patchkoria)
      Proceedings of the American Mathematical Society, 144 (2016), no. 9, 4099–4106.
      arXiv:1508.03129, pdf-file, published article
    8. Spectra of units for periodic ring spectra and group completion of graded E-infinity spaces
      Algebraic & Geometric Topology, 16 (2016), 1203–1251.
      arXiv:1111.6731, pdf-file, published article
    9. Localization sequences for logarithmic topological Hochschild homology
      (joint with John Rognes and Christian Schlichtkrull)
      Mathematische Annalen, 363 (2015), no. 3, 1349–1398.
      arXiv:1402.1317, pdf-file, published article
    10. Strictly commutative models for E-infinity quasi-categories
      (joint with Dimitar Kodjabachev)
      Homology, Homotopy and Applications, 17 (2015), no. 1, 121–128.
      arXiv:1408.0116, pdf-file, published article
    11. Derived logarithmic geometry I
      (joint with Timo Schürg and Gabriele Vezzosi)
      Journal of the Institute of Mathematics of Jussieu, 15 (2016), no. 2, 367–405.
      arXiv:1307.4246, pdf-file, published article
    12. Logarithmic structures on topological K-theory spectra
      Geometry & Topology, 18 (2014), 447–490.
      arXiv:1204.0699, pdf-file, published article
    13. Group completion and units in I-spaces
      (joint with Christian Schlichtkrull)
      Algebraic & Geometric Topology, 13 (2013), 625–686.
      arXiv:1111.6413, pdf-file, published article
    14. Diagram spaces and symmetric spectra
      (joint with Christian Schlichtkrull)
      Advances in Mathematics, 231 (2012), 2116–2193.
      arXiv:1103.2764, pdf-file, published article, corrections
    15. DG-algebras and derived A-infinity algebras
      Journal für die reine und angewandte Mathematik (Crelle's Journal), 639 (2010), 73–105.
      arXiv:0711.4499, pdf-file, published article
    16. Universal Toda brackets of ring spectra
      Transactions of the American Mathematical Society, 360 (2008), no. 5, 2767–2808.
      arXiv:math/0611808, pdf-file, published article
    17. On the algebraic K-theory of model categories
      Journal of Pure and Applied Algebra, 190 (2004), no. 1–3, 329–340.
      pdf-file, published article

    Notes from talks

    Usually, I give blackboard talks. Presentations from occasions where I used a projector can be found below. Moreover, this list contains a few extended abstracts and a link to a video of a talk.

    © 2019 Steffen Sagave
    Template design by Andreas Viklund