North Atlantic Noncommutative Geometry Seminar

22 listopada 2023 17:15
HERVÉ OYONO-OYONO (Université de Lorraine, Metz, France)
TBA

15 listopada 2023 17:15
PETER HOCHS (Radboud Universiteit, Nijmegen, Netherlands)
EQUIVARIANT ANALYTIC TORSION AND AN EQUIVARIANT RUELLE DYNAMICAL ZETA FUNCTION
Analytic torsion was introduced by Ray and Singer as a way to realise Reidemeister-Franz torsion analytically. (The equality was independently proved by Cheeger and Müller.) The Ruelle dynamical zeta function is a topological way to …

8 listopada 2023 17:15
MICHAEL FRANCIS (Western University, London, Canada)
THE TRANSVERSE ORIENTATION CLASS OF CERTAIN SINGULAR FOLIATIONS
In the 1980s, Connes defined the transverse orientation class of a transversely oriented foliation and showed it is a non-torsion element in K-theory. We will examine a special family of singular foliations for which a …

25 października 2023 17:15
STEFAAN CAENEPEEL (Vrije Universiteit Brussel, Belgium)
FORMAL THEORY OF MONADS, ADJUNCTIONS, ENTWINING STRUCTURES AND GALOIS THEORY
Brzeziński (2002) introduced Galois theory for corings with a fixed grouplike element. El Kaoutit and Gómez-Torrecillas (2003) generalized this to so-called comatrix corings. This establishes a general framework for existing Galois theories: classical Galois theory, Hopf-Galois theory, …

18 października 2023 17:15
MAGNUS B. LANDSTAD (Norges teknisk-naturvitenskapelige universitet, Trondheim, Norway)
EXOTIC GROUP ALGEBRAS, CROSSED PRODUCTS, AND COACTIONS
If G is a locally compact group, we have the full group C*-algebra C*(G) and the reduced C*_r(G). We call a C*-algebra properly between C*(G) and C*_r(G) exotic. Similarly, if G acts on a C*-algebra A we can form the full crossed product C*(GxA) and the …

11 października 2023 17:15
THERESE BASA LANDRY (University of California, Santa Barbara, USA)
SPECTRAL TRIPLES FOR NONCOMMUTATIVE SOLENOIDS
Noncommutative solenoids are inductive limit algebras built from rotation algebras. By viewing noncommutative solenoids as twisted group C*-algebras, we construct odd finitely summable spectral triples for noncommutative solenoids based on length functions of bounded doubling. …

4 października 2023 17:15
MANISH KUMAR (IMPAN, Warszawa, Poland)
FACTORIALITY AND FULLNESS OF q-ARAKI-WOODS VON NEUMANN ALGEBRAS
We discuss the factoriality, non-injectivity, and fullness questions of q-Araki-Woods von Neumann algebras, constructed by Hiai. These algebras are non-tracial counterparts of q-Gaussian algebras, which combine the q-deformations of free-group factors due to Bożejko, Kummerer and Speicher, and …

7 czerwca 2023 17:15
ROBERT YUNCKEN (Université Clermont Auvergne, France)
CRYSTALLIZING FUNCTIONS ON COMPACT LIE GROUPS
The theory of crystal bases, due to Kashiwara and Lusztig, is a means of simplifying the representation theory of semisimple Lie algebras by passing through quantum groups. Specifically, varying the parameter q of a quantized enveloping algebra, …

31 maja 2023 17:15
ROBERTO CONTI (Sapienza Università di Roma, Italy)
CLASSICAL SYMMETRIES OF NONCOMMUTATIVE SPACES: A GUIDED TOUR THROUGH THE CUNTZ ALGEBRA CASE
Multiplets of isometries with orthogonal ranges summing up to 1 were systematically used by Doplicher and Roberts in the early 70's  in their study of the superselection structure of Quantum Field Theory. Nowadays, the C*-algebra …

17 maja 2023 17:15
SOUMALYA JOARDAR (Indian Institute of Science Education and Research Kolkata, India)
EQUIVARIANT C*-CORRESPONDENCE
Let G be a compact quantum group. Then upon introducing the notion of a G-equivariant C*-correspondence and a G-C*-algebra, we shall show that a G-equivariant C*-correspondence makes the associated Pimsner algebra a G-C*-algebra. Moreover, for a Kac-type compact quantum group G, under …

10 maja 2023 17:15
DEVARSHI MUKHERJEE (Universidad de Buenos Aires, Argentina)
THE HOMOTOPY K-THEORY FOR NON-ARCHIMEDEAN BORNOLOGICAL ALGEBRAS
I will define non-Archimedean bivariant K-theory. This is the target of the universal functor on the category of complete, torsion free bornological Zp-algebras that satisfies homotopy invariance, stability and excision, and is a non-Archimedean analogue of …

26 kwietnia 2023 17:15
JULIEN BICHON (Université Clermont Auvergne, France)
THE FAITHFUL FLATNESS OF HOPF ALGEBRAS OVER COIDEAL SUBALGEBRAS WITH CONDITIONAL EXPECTATION
Faithful flatness is an algebraic concept arising from algebraic geometry and closely related to the question of forming ''good'' quotients. Also, it plays a key role in the noncommutative world, especially in Hopf-algebra theory. After …

19 kwietnia 2023 17:15
KONRAD AGUILAR (Pomona College, USA)
THE FELL TOPOLOGY AND THE MODULAR GROMOV-HAUSDORFF PROPINQUITY
Given a unital AF-algebra A equipped with a faithful tracial state, we endow each (norm-closed two-sided) ideal of A with a metrized quantum-vector-bundle structure. The ideals are canonically viewed as modules over A, in the sense of Latrémolière, using previous …

12 kwietnia 2023 17:15
STEFAN WALDMANN (Universität Würzburg, Germany)
CONVERGENCE OF STAR PRODUCTS: OLD AND NEW
In this talk, I will explain the issue of convergence for formal star products. While the theory of formal deformation quantizations of general Poisson manifolds is well-understood and explored by many people, for physical applications, formal power series in h are …

5 kwietnia 2023 17:15
SUTANU ROY (National Institute of Science Education and Research, India)
BRAIDED QUANTUM SYMMETRIES OF GRAPH C*-ALGEBRAS
In this talk, we will explain the existence of a universal braided compact quantum group acting on a graph C*-algebra in the twisted monoidal category of C*-algebras equipped with an action of the circle group. …