North Atlantic Noncommutative Geometry Seminar

Jan. 21, 2026, 5:15 p.m.
FABIO GAVARINI (Università di Roma Tor Vergata, Italy)
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Jan. 14, 2026, 5:15 p.m.
TOMASZ MASZCZYK (Uniwersytet Warszawski, Poland)
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Jan. 7, 2026, 5:15 p.m.
PIOTR M. HAJAC (IMPAN, Warszawa, Poland)
tba

Dec. 17, 2025, 5:15 p.m.
FRÉDÉRIC LATRÉMOLIÈRE (University of Denver, USA)
tba

Dec. 10, 2025, 5:15 p.m.
ALONSO DELFIN (University of Colorado, Boulder, USA)
tba

Dec. 3, 2025, 5:15 p.m.
YAN SOIBELMAN (Kansas State University, Manhattan, USA)
RIEMANN-HILBERT CORRESPONDENCE FROM THE POINT OF VIEW OF HOLOMORPHIC FLOER THEORY (RIEMANN-HILBERT CORRESPONDENCE FROM THE POINT OF VIEW OF HOLOMORPHIC FLOER THEORY)
To a complex symplectic manifold M one can assign two non-commutative spaces represented by two categories: one by the category of modules over the quantized sheaf of analytic functions on M, and one by the …

Nov. 26, 2025, 5:15 p.m.
WALTER VAN SUIJLEKOM (Radboud Universiteit, Nijmegen, The Netherlands)
A GENERALIZATION OF K-THEORY TO OPERATOR SYSTEMS (A GENERALIZATION OF K-THEORY TO OPERATOR SYSTEMS)
We propose a generalization of K-theory to operator systems. Motivated by spectral truncations of noncommutative spaces described by C*-algebras, and inspired by the realization of the K-theory of a C*-algebra as the Witt group of …

Nov. 19, 2025, 5:15 p.m.
KULUMANI M. RANGASWAMY (University of Colorado, Colorado Springs, USA)
NAIMARK'S PROBLEM FOR GRAPH C*-ALGEBRAS AND LEAVITT PATH ALGEBRAS (NAIMARK'S PROBLEM FOR GRAPH C*-ALGEBRAS AND LEAVITT PATH ALGEBRAS)
Naimark's problem asks whether a C*-algebra having a unique irreducible *-representation up to unitary equivalence is isomorphic to the C*-algebra of compact operators on some (not necessarily separable) Hilbert space. Here, we consider Naimark's problem …

Nov. 12, 2025, 5:15 p.m.
JENS KAAD (Syddansk Universitet, Odense, Denmark)
SPECTRAL LOCALIZERS IN KK-THEORY (SPECTRAL LOCALIZERS IN KK-THEORY)
In this talk, we compute the index homomorphism of even K-groups arising from a class in even KK-theory via the Kasparov product. Due to the seminal work of Baaj and Julg, under mild conditions on …

Nov. 5, 2025, 5:15 p.m.
MARIUSZ TOBOLSKI (Uniwersytet Wrocławski, Wrocław, Poland)
LOCALLY DERIVED GRAPHS (LOCALLY DERIVED GRAPHS)
Voltage and derived graphs (also called base and skew product graphs, respectively) were introduced by Gross and Tucker to study free actions of groups on graphs. These notions found applications in the theory of C*-algebras …

Oct. 29, 2025, 5:15 p.m.
ZACHARY MESYAN (University of Colorado, Colorado Springs, USA)
POSETS FROM LEAVITT PATH ALGEBRAS AND GRAPH INVERSE SEMIGROUPS (POSETS FROM LEAVITT PATH ALGEBRAS AND GRAPH INVERSE SEMIGROUPS)
We discuss parallel developments in the study of three types of well-known algebraic objects built from directed graphs: Leavitt path algebras, graph inverse semigroups, and graph C*-algebras. Similar results have been proved about those objects, …

Oct. 22, 2025, 5:15 p.m.
FRANCESCO D'ANDREA (Università di Napoli Federico II, Italy)
ON AMPLIFIED-GRAPH C*-ALGEBRAS AS CORES OF CUNTZ-KRIEGER ALGEBRAS (ON AMPLIFIED-GRAPH C*-ALGEBRAS AS CORES OF CUNTZ-KRIEGER ALGEBRAS)
Given a finite directed acyclic graph R, we construct from it two graphs: the graph E obtained by adding a loop at every vertex of R and the graph F obtained by replacing every edge …

Oct. 15, 2025, 5:15 p.m.
ELMAR WAGNER (Universidad Michoacana de San Nicolás de Hidalgo, Morelia, Mexico)
THE BGG RESOLUTION AND THE SPECTRUM OF DIRAC-LAPLACIANS ON NONCOMMUTATIVE LINE BUNDLES (THE BGG RESOLUTION AND THE SPECTRUM OF DIRAC-LAPLACIANS ON NONCOMMUTATIVE LINE BUNDLES)
The Bernstein-Gelfand-Gelfand resolution is a powerful tool to define natural elliptic first-order differential operators (Dirac operators) on irreducible flag manifolds. Heckenberger and Kolb showed in 2006 that the same construction applies to noncommutative irreducible flag …

Oct. 8, 2025, 5:15 p.m.
MICHAŁ ZIEMBOWSKI (Politechnika Warszawska, Warszawa, Poland)
FROM MATRICES TO LEAVITT PATH ALGEBRAS: BUILDING MAXIMAL COMMUTATIVE SUBALGEBRAS (FROM MATRICES TO LEAVITT PATH ALGEBRAS: BUILDING MAXIMAL COMMUTATIVE SUBALGEBRAS)
We move from the classical matrix setting to new constructions in Leavitt path algebras to investigate maximal commutative subalgebras. As a starting point, we recall the Schur-Jacobson viewpoint on maximal commutative subalgebras of matrix algebras, …

June 11, 2025, 5:15 p.m.
GILLES GONÇALVES DE CASTRO (Universidade Federal de Santa Catarina, Florianópolis, Brazil)
RELATION MORPHISMS OF DIRECTED GRAPHS (RELATION MORPHISMS OF DIRECTED GRAPHS)
Associating graph algebras to directed graphs leads to both covariant and contravariant functors from suitable categories of graphs to the category k-Alg of algebras and algebra homomorphisms. As both functors are often used at the …