Events - Page 37

Roberto Conti (La Sapienza, Rome) will give a talk with title "C*-algebras and Fourier theory"

Robert Yuncken (Univ. Clermont-Ferrand II, France) will give a talk with title: A groupoid approach to pseudodifferential operators

Abstract: Connes introduced the "tangent groupoid" of a manifold as a geometric device for linking a classical pseudodifferential operator to its symbol, yielding a novel proof of the Atiyah-Singer index theorem.  Since then, numerous variations on the tangent groupoid have been produced, each adapted to a different class of pseudodifferential operators.  In this talk we will consider the reverse problem: associating to a given tangent groupoid a pseudodifferential calculus.  We shall show that the kernels of classical pseudodifferential operators are precisely the essentially homogeneous fibrewise distributions on Connes' tangent groupoid.  This leads to a natural pseudodifferential calculus of subelliptic type on a manifold with a filtration on its Lie algebra of vector fields.

Fredrik Meyer, UiO, gives the Seminar in Algebra and Algebraic Geometry:

Modular curves VII

Comments on the Galilean limits of Maxwell's equations

Convex relaxation, graph cut and continuous max-flow algorithms for image processing and computer vision.

Pietro De Poi (Udine), gives the Seminar in Algebra and Algebraic Geometry:

A Severi type theorem on surfaces in P^6

Welcome to the SECOND conference on Stochastics of Environmental and Financial Economics. The conference will bring together leading researchers in the fields of stochastic analysis and finance to discuss recent developments and challenges with an edge towards energy, environmental and financial markets.

The conference is also a celebration of professor Bernt Øksendal's 70th anniversary. On Thursday April 23 the program of the conference will mark this big event with a selected list of speakers.

The conference is organized by the Center of Advanced Studies (CAS), Stochastics of Environmental and Financial Economics. Scientific organizers: Fred Espen Benth and Giulia Di Nunno (UiO)

Kristian Ranestad, UiO, gives the Seminar in Algebra and Algebraic Geometry:

Modular curves VI

Prof. Dr. Alois Gisler (ETH Zurich, RiskLab Switzerland) holds a seminar with the title "On the Development of the Swiss Solvency Test"

Prof. Dr. Alois Gisler (ETH Zurich, RiskLab Switzerland) holds a seminar with the title "The Reserve Risk of the Chain-Ladder Reserving Method from a New Perspective"

Réamonn Ó Buachalla (IMPAN) will give a talk with title: Noncommutative Kähler structures on quantum homogeneous spaces

Abstract:

Building on the definition of a noncommutative complex structure for a general algebra A, I will introduce the notion of a noncommutative Kähler structure for A. In the special case where A is a quantum homogeneous space, I show that many of the fundamental results of classical Kähler geometry follow from the existence of such a structure: Hodge decomposition, Serre duality, the Hard Lefschetz theorem, the Kähler identities, and collapse of the Frölicher spectral sequence at the first page. We then apply these results to Heckenberger and Kolb's differential calculus for quantum projective space, and show that they have cohomology groups of at least classical dimension. Time permitting, I will also discuss the relationship of this work to Connes proposal to study positive Hochschild cocycles as a starting point for noncommutative complex geometry, and Fröchlich, Grandjean, and Recknagel's definition of a Kähler spectral tuple.

Eduard Ortega, NTNU, will give a talk with title: Cuntz-Krieger uniqueness theorems

Abstract: I will make a little survey about Cuntz-Krieger uniqueness theorems and how they help to the study of the ideal structure of the rings to which one can apply them. In certain classes of (C*-)algebras this is described as topologically freeness or condition (L). However they are important classes of rings for which are not known Cuntz-Krieger type theorems. I will present a class of rings, that generalize Leavitt path algebras and Passman crossed products, for which I can totally characterize the Cuntz-Krieger uniqueness theorem.

Parameter-robust finite element discretization and its preconditioning for Biot's consolidation model in poroelasticity

Erik Bédos will give a talk with title: On the Fourier-Stieltjes algebra of a C*-dynamical system

Abstract: When G is a discrete group, its Fourier-Stieltjes algebra B(G) may be described as the set of coefficient functions associated with unitary representations of G on Hilbert spaces. In a similar way, if Sigma=(A, G, alpha, sigma) is a unital discrete twisted C*-dynamical system, one may let the Fourier-Stieltjes algebra B(Sigma) consist of the functions from G x A into A that arise as coefficient functions of equivariant representations of Sigma on Hilbert A-modules. We will explain how B(Sigma) may be organized as an algebra with conjugation, and show that it may be represented as completely bounded multipliers on the full crossed product C*(Sigma). (This is also known to be true for the reduced crossed product). This is part of an ongoing project with Roberto Conti (Rome).

Arvid Siqveland, Høgskolen i Buskerud og Vestfold, gives the Seminar in Algebra and Algebraic Geometry:

Modular curves V

These are the fifth and and the sixth lectures given by Anders Hansen (Cambridge Univ. and UiO) on Compressed sensing - Theory and Applications.

These are the third and fourth lectures given by Anders Hansen (Cambridge Univ. and UiO) on Compressed sensing - Theory and Applications.

These are the first two of six 45-min. lectures given by Anders Hansen (Cambridge Univ. and UiO) on Compressed sensing - Theory and Applications.

Fredrik Meyer, UiO, gives the Seminar in Algebra and Algebraic Geometry:

Modular curves IV

Olav Breivik (Dept. of Math., UiO ) gives a seminar in room 107, 1st floor N.H. Abels House at 14:15 March 17th:  Bycatch of juvenile cod in the Barents Sea shrimp fishery

Arne B. Sletsjøe, UiO, gives the Seminar in Algebra and Algebraic Geometry:

Modular curves III

Sam Sanders, Ghent and Munich, will give a lecture with the tittle

On the contingency of predicativism.

Franz Luef (NTNU) will give  a talk with title "Sigma-models solitons on noncommutative spaces"

Abstract: Results from time-frequency analysis and Gabor analysis allow the construction of new classes of sigma-model solitons over the Moyal plane and over noncommutative tori, taken as source spaces, with a target space made of two points. A natural action functional leads to self-duality equations for projections in the source algebra. Solutions, having non-trivial topological content, are constructed via suitable Morita duality bimodules. This is joint work with L. Dabrowski and G. Landi.