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


Autumn semester 2020/21
  • I am not teaching any courses this semester.
Teaching in previous terms


  1. Homotopical and operator algebraic twisted K-theory
    (joint with Fabian Hebestreit)
    arXiv:1904.01872, pdf-file

Publications and accepted papers

(in reverse chronological order of acceptance)

  1. A strictly commutative model for the cochain algebra of a space
    (joint with Birgit Richter)
    Accepted for publication in Compositio Mathematica
    arXiv:1801.01060, pdf-file
  2. Multiplicative parametrized homotopy theory via symmetric spectra in retractive spaces
    (joint with Fabian Hebestreit and Christian Schlichtkrull)
    Forum of Mathematics, Sigma, 8 (2020), e16, 84 pages
    arXiv:1904.01824, pdf-file, published article (open access)
  3. Homotopy invariance of convolution products
    (joint with Stefan Schwede)
    International Mathematics Research Notices (2020), doi:10.1093/imrn/rnz334, 1–47
    arXiv:1907.05188, pdf-file, published article (open access)
  4. 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)
  5. 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
  6. Generalized Thom spectra and their topological Hochschild homology
    (joint with Samik Basu and Christian Schlichtkrull)
    Journal of the Institute of Mathematics of Jussieu, 19 (2020), no. 1, 21-64
    arXiv:1608.08388, pdf-file, published article
  7. 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
  8. 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
  9. 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
  10. 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
  11. 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
  12. 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
  13. 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
  14. Logarithmic structures on topological K-theory spectra
    Geometry & Topology, 18 (2014), 447–490.
    arXiv:1204.0699, pdf-file, published article
  15. 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
  16. Diagram spaces and symmetric spectra
    (joint with Christian Schlichtkrull)
    Advances in Mathematics, 231 (2012), 2116–2193.
    arXiv:1103.2764, pdf-file, published article, corrections
  17. 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
  18. 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
  19. 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.

© 2020 Steffen Sagave
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