Tidligere arrangementer - Side 117
Friday seminar by Jeffrey Hutchings
P? Partnerforums siste m?te i ?konomistyringsnettverket s? vi p? statlig styring av selskaper med sektorpolitiske m?l.
Hvordan er balansen mellom tett styring fra departementene og selskapenes egen handlefrihet?
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.
Friday seminar by Barbara Bramanti
CEES Extra seminar by Ulf Büntgen
Friday seminar by Torstein Tengs
H?kon Dahle, forsker, Institutt for teoretisk astrofysikk.
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
Friday seminar by Thorsten Reusch
Claus Madsen, senior advisor at the European Southern Observatory (ESO).
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
Friday seminar by Wayne Getz
Christine Lindstr?m, f?rsteamanuensis i naturfag, H?gskolen i Oslo og Akershus.
The seminar on the slime mold Dictyostelium discoideum will be held by Dr Monica Hagedorn.
Dr Monica Hagedorn is a distinguished researcher from Bernhard Nocht Institute for Tropical Medicine, Hamburg, Germany. She has several publications describing how the social amoebae D. discoideum reveal new knowledge in infectious diseases.
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
Friday seminar by Geir Huse. (NOTE THE TIME AND VENUE!)
Yabebal Fantaye, post doc. ved Institutt for teoretisk astrofysikk fra november.
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 R?rdam, and by Yasuhiko Sato).