Events - Page 43
Marcus K. V. Eriksson (Universitetet i Oslo) holder et seminar med tittelen: A valuation model with minimal and maximal constraints for swing options.
Roberto Conti, Universita La Sapienza (Rome), Italy, will give a talk with title: The dark side of the Cuntz algebras
Abstract: We provide an overview of our recent work on the automorphism group of Cuntz algebras and discuss a number of open problems. (Joint work with J.H. Hong and W. Szymanski).
Benjamin Holcblat (Department of Financial Economics, BI) will talk about
A Classical Moment-Based Approach with Bayesian Properties: Econometric Theory and Empirical Evidence from Asset Pricing
Gunther Cornelissen, Utrecht University (The Netherlands) will give a talk with title "Dynamical systems and point counting"
Abstract: Counting the points of a curve over finite fields doesn't determine the curve up to isomorphism; this is analogous to the famous fact that you cannot "hear the shape of a drum". I will show how to remedy this by counting points in a weighted way (namely, using abelian L-series). The method of proof is through the theory of dynamical systems, and - curiously - arose from a study of a quantum statistical mechanical system.
Makoto Yamashita, p.t. University of Copenhagen, will give a talk with title "Tannaka-Krein duality of quantum homogeneous spaces"
Abstract: We study ergodic actions of compact quantum groups on operator algebras (quantum homogeneous spaces) from the categorical point of view. The language of Rep(G)-module C*-categories gives a reconstruction theorem of quantum homogeneous spaces, which also captures the equivariant Morita equivalence and the equivariant homomorphisms. For the case of quantum SU(2), the universality of Rep(SUq(2)) allows us to obtain a combinatorial description of quantum homogeneous spaces and their properties. Based on joint work with Kenny De Commer (arXiv:1211.6552, arXiv:1212.3413).
Rama Cont (Imperial College) holder et seminar med tittelen: Functional Ito calculus and functional Kolmogorov equations
Magnus Dahler Norling, UiO, will give a talk with title: The K-theory of some reduced inverse semigroup C*-algebras
Abstract: We use a recent result by Cuntz, Echterhoff and Li about the K-theory of certain reduced C*-crossed products to describe the K-theory of C*_r(S) when S is an inverse semigroup satisfying certain requirements. A result of Milan and Steinberg allows us to show that C*_r(S) is Morita equivalent to a crossed product of the type handled by Cuntz, Echterhoff and Li. We apply the results to graph inverse semigroups and the inverse semigroups of one-dimensional tilings.
Michael Scheuerer will talk about (Institute of Applied Mathematics, Heidelberg University)
Statistical post-processing of weather forecasts: The importance of spatial modeling
Program for the seminar in Logic, Spring 2013
Donna Mary Salopek (Uni. South Wales) holder et seminar med tittelen: Stochastic Evolution Equations driven by Liouville Fractional Brownian motion
Benedykt Szozda (Uni. Aarhus) holder et seminar med tittelen: Anticipative extension of the Ito integral
Thomas Jaki (Department of Mathematics and Statistics, Lancaster University) will talk about
Designing multi-arm multi-stage clinical studies
Matthew Sperrin (Department of Mathematics and Statistics, Lancaster University) will talk about
Modelling the effect of interventions on onset and progression of chronic disease
Fred Shultz, Wellesley College, USA will give a talk with title "Decomposing separable states".
This is the first in a joint seminar series organised by the Operator Algebra group (UiO), Several Complex Variable group (UiO) and the CAS group. The plan is to have seminars every other week.
Abstract: This talk will begin with a brief introduction to entanglement and its applications, since that motivates the mathematics to be discussed. In the title of this talk, a state is a positive linear functional on the tensor product of the algebras of m x m and n x n complex matrices. Such a state is separable if it is a convex combination of product states. An interesting open problem is to give a useful criterion for a state to be separable. A related problem is to give a systematic way to find a decomposition of a separable state into a convex combination of product states. This talk will describe such a decomposition for a class of separable states that is of both physical and mathematical interest. This decomposition is also applicable to a class of completely positive maps (which correspond to certain quantum channels). This is joint work with Erik Alfsen.
Paul Kruehner, MAWREM/CMA, holder et seminar med tittelen: Subordination of Hilbert space valued Lévy processes
Magnus Landstad (NTNU) will give a talk with title: Exotic group C*-algebras and noncommutative duality.
Abstract: It has long been known that for a (non-amenable) locally compact group G there are many C*-algebras between the full and reduced group C*-algebra. First I will discuss to what extent these intermediate algebras can be called group C*-algebras. Then I will look at algebras between the full and reduced crossed product, and the various types of coactions (full, maximal, normal) a group can have. To make arguments a little simpler, we shall assume G to be discrete.
Abstract: In groundbreaking work Thomason establishes a fundamental comparison between Bott-inverted algebraic K-theory and étale K-theory with finite coefficients. Over the complex numbers, Walker has shown how to deduce Thomason's theorem using a semi-topological K-homology theory. In joint work with J. Hornbostel we establish an equivariant generalization of Walker's Fundamental Comparison Theorem and use it to deduce the equivariant version of Thomason's theorem for complex varieties with action by a finite group.
Salvador Ortiz-Latorre, EMMOS/CMA, holder et seminar med tittelen: A second order approximation of the continuous time filtering problem
Yoshiko Ogata, University of Tokyo, will give a talk with title: Approximating macroscopic observables in quantum spin systems with commuting matrices
Abstract: Macroscopic observables in a quantum spin system are spatial means of local observables in a UHF algebra. One of their properties is that they commute asymptotically as the system size goes to infinity. It is not true that any given set of asymptotically commuting matrices can be approximated by commuting ones in the norm topology. The main statement of this talk is that this is true for macroscopic observables.
Bin Yu (Departments of Statistics and Electrical Engineering & Computer Science, UC Berkeley) will talk about
Spectral clustering and high-dim stochastic block model for undirected and directed graphs
Jyotishman Bhowmick, UiO, will give a talk with title: Deformation of operator algebras by Borel cocycles
Abstract:Given a coaction of a locally compact group on a C^* algebra and fixing a cocycle on G, we discuss a method to deform A into another C^* algebra, thus generalizing the works of Kasprzak, Yamashita and Rieffel. This is a joint work with S. Neshveyev and A.S. Sangha.
Krzystzof Paczka, CMA, holder et seminar med tittelen: G-Lévy processes: Ito calculus, jumps diffusions and robust optimal control
Fabio Divino (University of Molise, Italy) will talk about
MCMC computation for Bayesian modeling of presence-only data
Stuart White (University of Glasgow, UK) will talk on "Z-stability and central sequences".
Abstract: Over recent years, tensorial absorption of the Jiang-Su algebra $\mathcal Z$ has become a particularly prominent property of $C^*$-algebras. In this talk, I'll explain what this means, and why this is the case; I'll also discuss methods for establishing ``$\mathcal Z$''-stability using central sequence, and some more general properties of central sequence algebras. The talk will end with a recent result showing that for a simple separable unital nuclear C*-algebra, whose extremal traces are compact and of finite covering dimension $\mathcal Z$-stability can be detected by a comparison property of the Cuntz semigroup (this result is joint work with Andrew Toms and Wilhelm Winter, which has also been independently discovered by Eberhard Kirchberg and Mickael Rørdam, and by Yasuhiko Sato).