Preprints
$G$-kernels and Crossed Modules
Girón Pacheco, Sergio; Izumi, Masaki; Pennig, Ulrich
Girón Pacheco, Sergio; Izumi, Masaki; Pennig, Ulrich
Computing Connection Matrices of Conley Complexes via Algebraic Morse Theory
Torras-Casas, Álvaro; Yim, Ka Man; Pennig, Ulrich
Torras-Casas, Álvaro; Yim, Ka Man; Pennig, Ulrich
Units of $\mathbb{Z}/p\mathbb{Z}$-equivariant K-theory and bundles of UHF-algebras
Bianchi, Valerio; Pennig, Ulrich
Bianchi, Valerio; Pennig, Ulrich
A survey on operator K-theory via homotopical algebra
Bunke, Ulrich; Land, Markus; Pennig, Ulrich
Bunke, Ulrich; Land, Markus; Pennig, Ulrich
Twisted K-theory with coefficients in C*-algebras
Pennig, Ulrich
Pennig, Ulrich
Publications
Spectral Sequence Computation of Higher Twisted K-groups of SU(n)
Evans, David E.; Pennig, Ulrich
Comm. Amer. Math. Soc. 5 (2025), 897-942, doi: 10.1090/cams/60
Evans, David E.; Pennig, Ulrich
Comm. Amer. Math. Soc. 5 (2025), 897-942, doi: 10.1090/cams/60
Spanier-Whitehead K-Duality and Duality of Extensions of C*-algebras
Pennig, Ulrich; Sogabe, Taro
International Mathematics Research Notices, 2024; rnae242, doi: 10.1093/imrn/rnae242
Pennig, Ulrich; Sogabe, Taro
International Mathematics Research Notices, 2024; rnae242, doi: 10.1093/imrn/rnae242
Bundles of strongly self-absorbing C*-algebras with a Clifford grading
Dadarlat, Marius; Pennig, Ulrich
J. Math. Soc. Japan 77(4): 1103-1136 (October, 2025). DOI: 10.2969/jmsj/92259225
Dadarlat, Marius; Pennig, Ulrich
J. Math. Soc. Japan 77(4): 1103-1136 (October, 2025). DOI: 10.2969/jmsj/92259225
Computing cohomology groups that classify bundles of strongly self-absorbing C*-algebras
Dadarlat, Marius; McClure, James E.; Pennig, Ulrich
Journal of Topology and Analysis, doi: 10.1142/S1793525324500110
Dadarlat, Marius; McClure, James E.; Pennig, Ulrich
Journal of Topology and Analysis, doi: 10.1142/S1793525324500110
Interleaving Mayer-Vietoris spectral sequences
Torras, Álvaro; Pennig, Ulrich
Algebraic & Geometric Topology 24 (2024) 4265–4306 DOI: 10.2140/agt.2024.24.4265
Torras, Álvaro; Pennig, Ulrich
Algebraic & Geometric Topology 24 (2024) 4265–4306 DOI: 10.2140/agt.2024.24.4265
Equivariant higher Dixmier-Douady Theory for circle actions on UHF-algebras
Evans, David; Pennig, Ulrich
Adv. Math., Vol. 410 (2022), 108745, doi: 10.1016/j.aim.2022.108745
Evans, David; Pennig, Ulrich
Adv. Math., Vol. 410 (2022), 108745, doi: 10.1016/j.aim.2022.108745
Equivariant higher twisted K-theory of SU(n) for exponential functor twists
Evans, David E.; Pennig, Ulrich
J. Topology (2022), 15: 896-949, doi:10.1112/topo.12219
Evans, David E.; Pennig, Ulrich
J. Topology (2022), 15: 896-949, doi:10.1112/topo.12219
Exponential Functors, R-matrices and Twists
Pennig, Ulrich
Algebraic & Geometric Topology 20 (2020) 1279–1324, doi: 10.2140/agt.2020.20.1279
Pennig, Ulrich
Algebraic & Geometric Topology 20 (2020) 1279–1324, doi: 10.2140/agt.2020.20.1279
Yang-Baxter representations of the infinite symmetric group
Lechner, Gandalf; Pennig, Ulrich; Wood, Simon
Adv. Math., Vol. 355, 2019, 106769, doi: 10.1016/j.aim.2019.106769
Lechner, Gandalf; Pennig, Ulrich; Wood, Simon
Adv. Math., Vol. 355, 2019, 106769, doi: 10.1016/j.aim.2019.106769
Connective C*-algebras
Dadarlat, Marius; Pennig, Ulrich
J. Funct. Anal. (2017), Vol 272, Issue 12; doi: 10.1016/j.jfa.2017.02.009
Dadarlat, Marius; Pennig, Ulrich
J. Funct. Anal. (2017), Vol 272, Issue 12; doi: 10.1016/j.jfa.2017.02.009
Locally trivial W*-bundles
Evington, Samuel; Pennig, Ulrich
Int. J. Math. (2016), Vol. 27, Issue 11; doi: 10.1142/S0129167X16500889
Evington, Samuel; Pennig, Ulrich
Int. J. Math. (2016), Vol. 27, Issue 11; doi: 10.1142/S0129167X16500889
Deformations of Wreath Products
Dadarlat, Marius; Pennig, Ulrich; Schneider, Andrew.
Bull. London Math. Soc., Vol. 49, Issue 1; doi: 10.1112/blms.12008
Dadarlat, Marius; Pennig, Ulrich; Schneider, Andrew.
Bull. London Math. Soc., Vol. 49, Issue 1; doi: 10.1112/blms.12008
Crossed module actions on continuous trace C*-algebras
Meyer, Ralf; Pennig, Ulrich
Comm. Math. Phys. (2016), 346(1), 115-142; doi: 10.1007/s00220-016-2638-3
Meyer, Ralf; Pennig, Ulrich
Comm. Math. Phys. (2016), 346(1), 115-142; doi: 10.1007/s00220-016-2638-3
Deformations of nilpotent groups and homotopy symmetric C*-algebras
Dadarlat, Marius; Pennig, Ulrich
Math. Ann. (2017) 367: 121; doi: 10.1007/s00208-016-1379-0
Dadarlat, Marius; Pennig, Ulrich
Math. Ann. (2017) 367: 121; doi: 10.1007/s00208-016-1379-0
A noncommutative model for higher twisted K-theory
Pennig, Ulrich
J. Topology (2016) 9 (1): 27-50; doi: 10.1112/jtopol/jtv033
Pennig, Ulrich
J. Topology (2016) 9 (1): 27-50; doi: 10.1112/jtopol/jtv033
A Dixmier-Douady theory for strongly self-absorbing C*-algebras II: the Brauer group
Dadarlat, Marius; Pennig, Ulrich
J. Noncommut. Geom. 9 (2015), no. 4, 1137 - 1154
Dadarlat, Marius; Pennig, Ulrich
J. Noncommut. Geom. 9 (2015), no. 4, 1137 - 1154
Unit spectra of K-theory from strongly self-absorbing C*-algebras
Dadarlat, Marius; Pennig, Ulrich
Algebraic and Geometric Topology 15 (2015), no. 1, 137 - 168.
Dadarlat, Marius; Pennig, Ulrich
Algebraic and Geometric Topology 15 (2015), no. 1, 137 - 168.
Twisted K-theory and obstructions against positive scalar curvature metrics
Pennig, Ulrich
Journal of K-Theory 14 (2014), 47 - 71
Pennig, Ulrich
Journal of K-Theory 14 (2014), 47 - 71
A Dixmier-Douady theory for strongly self-absorbing C*-algebras
Dadarlat, Marius; Pennig, Ulrich
J. Reine Angew. Mathematik; doi: 10.1515/crelle-2014-0044
Dadarlat, Marius; Pennig, Ulrich
J. Reine Angew. Mathematik; doi: 10.1515/crelle-2014-0044
Quasi-multipliers of Hilbert and Banach C*-bimodules
Pavlov, Alexander; Pennig, Ulrich; Schick, Thomas Schick
Math. Scand. 109 (2011), no. 1, 71 - 92.
Pavlov, Alexander; Pennig, Ulrich; Schick, Thomas Schick
Math. Scand. 109 (2011), no. 1, 71 - 92.
The classification of non-local chiral CFT with c < 1
Kawahigashi, Yasuyuki; Longo, Roberto; Pennig, Ulrich; Rehren, Karl-Henning
Comm. Math. Phys. 271 (2007), no. 2, 375 - 385.
Kawahigashi, Yasuyuki; Longo, Roberto; Pennig, Ulrich; Rehren, Karl-Henning
Comm. Math. Phys. 271 (2007), no. 2, 375 - 385.
Lecture Notes
Algebraic Topology
This is the link to lecture notes for the algebraic topology course I gave in the Spring Semester 2017 at Cardiff University.
This is the link to lecture notes for the algebraic topology course I gave in the Spring Semester 2017 at Cardiff University.
K-Theorie und die Hopf-Invariante
These are the notes (in german) for the lecture "K-Theory and the Hopf invariant" I gave in Münster in the Summer Semester 2015.
These are the notes (in german) for the lecture "K-Theory and the Hopf invariant" I gave in Münster in the Summer Semester 2015.
Slides
Bundles of C*-Algebras - An introduction to Dixmier-Douady Theory
Slides of a talk I gave in the NYC Noncommutative Geometry Seminar
16th February 2022
Slides of a talk I gave in the NYC Noncommutative Geometry Seminar
16th February 2022
Equivariant higher Dixmier-Douady theory for circle actions
Slides of a talk I gave in the Oberseminar Globale Analysis
9th February 2022, Universität Regensburg via Zoom
Slides of a talk I gave in the Oberseminar Globale Analysis
9th February 2022, Universität Regensburg via Zoom
Fell bundles, Dixmier-Douady theory and higher twists
Slides of a talk I gave in the workshop Actions of Tensor Categories on C*-Algebras
January, 28th 2021, Institute for Pure and Applied Mathematics (IPAM) via Zoom
Slides of a talk I gave in the workshop Actions of Tensor Categories on C*-Algebras
January, 28th 2021, Institute for Pure and Applied Mathematics (IPAM) via Zoom
Bundles of C*-Algebras - An introduction to Dixmier-Douady Theory
Slides of a talk I gave in the UK Virtual Operator Algebras Seminar 2020 on Zoom
13th August 2020
Slides of a talk I gave in the UK Virtual Operator Algebras Seminar 2020 on Zoom
13th August 2020
Loops, Groups and Twists - The role of K-theory in mathematical physics
Slides of a talk I gave at the Pure Maths Colloquium in Southampton
October 11th, 2019, Southampton
Slides of a talk I gave at the Pure Maths Colloquium in Southampton
October 11th, 2019, Southampton
Waldhausen's $S_•$-construction
Handwritten notes (in german) of a talk about simplicial sets, spaces and categories and the $S_•$-construction. This was the teaching examination part of my habilitation.
July 11th, 2016, Münster
Handwritten notes (in german) of a talk about simplicial sets, spaces and categories and the $S_•$-construction. This was the teaching examination part of my habilitation.
July 11th, 2016, Münster
The Erdös-Szekeres Convex Polygon Problem
Slides of my habilitation colloquium talk about Andrew Suk's improvements on the Erdös-Szekeres Convex Polygon Problem.
The ideas contained in the proof are entirely his, all mistakes and typos on the slides are my fault.
July 13th, 2016, Münster
Slides of my habilitation colloquium talk about Andrew Suk's improvements on the Erdös-Szekeres Convex Polygon Problem.
The ideas contained in the proof are entirely his, all mistakes and typos on the slides are my fault.
July 13th, 2016, Münster
Units of K-Theory via strongly self-absorbing C*-algebras
Conference "Twists, generalised cohomology and applications"
October 14th to 18th, 2013, Münster
Notes of a talk about the same topic in the topology seminar at Berkeley
Conference "Twists, generalised cohomology and applications"
October 14th to 18th, 2013, Münster
Notes of a talk about the same topic in the topology seminar at Berkeley
C*-algebras
Notes of an introductory talk about C*-algebras and their K-theory
talk at the topology seminar at Berkeley
Notes of an introductory talk about C*-algebras and their K-theory
talk at the topology seminar at Berkeley
Modular tensor categories from quantum doubles of finite groups
Notes about the representation category of the quantum double of finite groups
Lecture about "Topological Quantum Field Theories" during the winter semester 2011
Notes about the representation category of the quantum double of finite groups
Lecture about "Topological Quantum Field Theories" during the winter semester 2011
Gauge theory with finite gauge group
Notes about Dijkgraaf-Witten theory in two dimensions, based on the paper by Freed and Quinn
Lecture about "Topological Quantum Field Theories" during the winter semester 2011
Notes about Dijkgraaf-Witten theory in two dimensions, based on the paper by Freed and Quinn
Lecture about "Topological Quantum Field Theories" during the winter semester 2011
A Non-commutative Model for Higher Twisted K-Theory
Slides of a talk that I gave during the 31st Summer Conference on Topology and its Applications in Leicester
in the section "Topological Methods in Algebra and Analysis"
Slides of a talk that I gave during the 31st Summer Conference on Topology and its Applications in Leicester
in the section "Topological Methods in Algebra and Analysis"
Von Neumann algebras in physics: a rough sketch of algebraic quantum field theory
Seminar about "Von Neumann Algebras" organized by Raimar Wulkenhaar and me
Seminar about "Von Neumann Algebras" organized by Raimar Wulkenhaar and me
Von Neumann algebras and the Connes fusion tensor product
Winter school "From field theories to elliptic objects"
February 28th to March 4th, 2006, Schloss Mickeln, Düsseldorf
Winter school "From field theories to elliptic objects"
February 28th to March 4th, 2006, Schloss Mickeln, Düsseldorf
Habilitation, Dissertation, Diploma Thesis and all that...
