Tidlegare gjesteforelesninger og seminarer - Side 75

Joint seminar of the Theory group and the AMCS group

Speaker: Professor Constantino Tsallis, Brazilian Center for Physics Research and National Institute of Science and Tech  

Abstract: The Kolmogorov decomposition of positive scalar valued kernels has played an important role in applications of operator theory to function theory.  It has been vastly generalised, finding its apotheosis in the result of Baretto, Bhat, Liebscher and Skeide which states that a positive $L(A,B)$-valued kernel, $A$ and $B$ $C^*$-algebras, has a Kolmogorov decomposition if and only if it is completely positive; that is, the restriction of the kernel to any finite set of index points gives a completely positive map.  The result may be viewed as a generalisation of the Stinespring dilation theorem from single point to multi-point index sets.  This talk presents the analogue of the Haagerup-Paulsen-Wittstock decomposition theorem for $L(A,B)$-valued kernels (where now $B$ is assumed to be injective).  It happens that in general complete boundedness of the kernel (ie, complete boundedness of the map resulting from restriction of the kernel to any finite index set) is not quite enough to ensure a decomposition: a certain regularity condition must also hold.  This condition can be seen to be automatic if the kernel is completely positive or the index set is countable.  This is joint work with Tirthankar Bhattacharyya and Chris Todd.  

Hans Pecseli, professor, Fysisk institutt, UiO.

Abstract: In topology, there is a correspondence between generalized cohomology theories (in the sense of the Eilenberg-Steenrod axioms) on one hand and spectra on the other hand, the latter being objects in the stable homotopy category SH. In algebraic geometry and motivic homotopy theory, the situation is much more complicated in several ways. Firstly, there are many stable homotopy categories, one for each scheme, and various functors between them. Secondly, there are many sets of axioms for what a cohomology theory should be (Weil cohomology, Bloch-Ogus cohomology, oriented cohomology, ...) and a huge zoo of cohomology theories. The aim of the talk will be to give an overview of all generalized cohomology theories in algebraic geometry, using the language of motivic stable homotopy theory. 

Jukka Lempa, EMMOS/CMA, holder et seminar med tittelen: Some Properties of Harmonic Functions for Diffusion Processes

Friday seminar by Hervé Seligmann

NOTE: This will NOT be a Friday Seminar, but rather a Friday Tutorial. It will be two hours rather than one, using blackboard and live demos rather than slides.

Abstract: Klassifikasjon av mangfoldigheter leder ofte til spørsmål om h-kobordente mangfoldigheter er homeomorfe eller ikke. Jeg skal presentere noen nye resultater av Slawomir Kwasik og meg selv om dette viktige problemet. 

Øystein Sørensen (Department of Biostatistics, UiO) will talk about

Penalized Regression with Measurement Error

Kavliprisene er et samarbeid mellom Det norske videnskaps-akademi, Kavli Foundation (USA) og Kunnskapsdepartementet. Dette er tredje året prisene deles ut, og utdelingen finner sted i Oslo den 4. september 2012. I tillegg til selve utdelingen er det flere Kavlipris-arrangementer den første uken i september.

Atsushi Takeuchi (Uni. Osaka City) holder et seminar med tittelen: Positivity of Densities for Stochastic Differential Equations Driven by Gamma Processes

Over the last decades important methodological advances have been made for designing and analysing nested case-control and case-cohort studies. While some of these methodologies need further developments before they can be widely used, others have matured to a level that makes them ready to use in epidemiological practice. The focus of the workshop is on the methodologies that are ready to use. The workshop is aimed at biostatisticians and epidemiologists who work with population registry data and large cohorts studies. It is assumed that the participants are familiar with cohort and classical case-control studies and the regression models used to analyse them (logistic regression and Cox regression).

Patrick J. Lynett is from the University of Southern California.

The seminar language this term will be English, see the corresponding webpage in English

Dávid Kunszenti-Kovács, Tübingen University (Germany) will give a talk with title "The Jacobs-deLeeuw-Glicksberg decomposition and ergodic theorems".

Abstract: We present the classical decomposition theorem for contractions on Hilbert spaces due to Jacobs, deLeeuw and Glicksberg, and show how it can be used to prove ergodic theorems. We then prove a new version of this decomposition, adapted to the context of W*-algebras, with consequences for W*-dynamical systems. Finally we take a look at how the characterizations given in the original decomposition theorem can be further strengthened.  

John Quigg, University of Arizona (Tempe), USA, will give a talk with title "Exotic group C*-algebras"

Abstract: We study C*-algebras between C*(G) and C*_r(G), focusing on the aspects relevant to noncommutative crossed-product duality.  

I august 2012 er det femti år siden Norge ble en romnasjon. Inngangen i 1962 ble den første forskningsraketten, Ferdinand 1, som ble skutt opp fra Andøya Rakettskytefelt. Dette blir markert på Andøya den 16.-19. august med konferanser, seminar og et åpent program. Instituttene for geofag, teoretisk astrofysikk, og fysikk vil delta under markeringen under parolen UiO i rommet.

CEES Extra seminar by Marek Kwiatkowski (NOTE THE TIME AND VENUE!)

Roberto Silvotti, L' Osservatorio Astrofisico di Torino

Friday seminar by Jason R. Miller from J. Craig Venter Institute

Rand Kwong Yew Low (UQ Business School, University of  Queensland, Brisbane) will talk about

Portfolio optimization based on pair-copula constructions

Friday seminar by Jeffrey A. Hutchings