Forskningsarrangementer

Pågående

Tid og sted: 25. sep. 2018 09:15 - 15:45, Hotel Bristol, Oslo

Matematisk Institutt ved Universitetet i Oslo ønsker deg med dette velkommen til en forsikringsdag der noen av landets topp fagfolk vil ta deg med gjennom noen av de mest dagsaktuelle emner innen forsikring.

Vi er er landets ledende leverandør av aktuarer og finansmatematikere til forsikrings- og finansnæringen og også det ledende forskningsenter på disse feltene.

Kommende

Tid og sted: 25. sep. 2018 14:15 - 15:15, Niels Henrik Abels hus, 8th floor

Giuliana Cortese (Department of Statistical Sciences, University of Padova) will give a talk on September 25th at 14:15 in the Seminar Room 819, Niels Henrik Abels hus, 8th floor.

Tid og sted: 28. sep. 2018 09:15 - 10:00, Niels Henrik Abels hus, 8th floor

Rebecka Jörnsten (Division of Applied Mathematics and Statistics, University of Gothenburg / Chalmers University of Techology) will give a talk on September 28th at 9:15 in the Seminar Room 819, Niels Henrik Abels hus, 8th floor.

Tid og sted: 1. okt. 2018 14:15 - 15:15, Niels Henrik Abels hus, 8th floor

Ingrid Van Keilegom (Department of Statistical Sciences, University of Padova) will give a talk on Monday, October 1st at 14:15 in the Seminar Room 819, Niels Henrik Abels hus, 8th floor.

Tid og sted: 9. okt. 2018 14:15 - 15:15, Niels Henrik Abels hus, 8th floor

Emanuele Gramuglia (Department of Mathematics, University of Oslo) will give a talk on October 9th at 14:15 in the Seminar Room 819, Niels Henrik Abels hus, 8th floor.

Tidligere

Tid og sted: 19. sep. 2018 11:15 - 12:00, NHA 108

Prof. Masaki Izumi, Kyoto University, Japan, will give a talk with title:

The classification of poly-Z group actions on Kirchberg algebras

Abstract: We completely classify outer actions of a poly-Z group G on any Kirchberg algebra A in terms of a principal Aut(A x K)-bundle over the classifying space BG. This is joint work with Hiroki Matui.

 

 

Tid og sted: 19. sep. 2018 10:15 - 11:00, NHA 108

Becky Armstrong, University of Sydney, Australia, will give a talk with title:

Simple graph algebras

Abstract: Since their introduction twenty years ago, C*-algebras associated to directed graphs have become a popular tool for investigating various classes of C*-algebras, because analytical properties of these C*-algebras depend on much simpler combinatorial properties of the underlying graphs. One such analytical property is simplicity, which plays a fundamental role in the classification program for C*-algebras. In this talk I will first recall the characterisation of simplicity for directed graph C*-algebras. I will then describe the results of my PhD research, in which I characterise simplicity of twisted C*-algebras of topological higher-rank graphs in terms of the underlying graphical and cohomological data. These C*-algebras are constructed using groupoid techniques for the purpose of this simplicity characterisation, but I will also briefly describe two product-system models for twisted C*-algebras of topological higher-rank graphs. (This is joint work with my PhD supervisors, Nathan Brownlowe and Aidan Sims.)

 

 

Tid og sted: 17. sep. 2018 13:45 - 15:45, Niels Henrik Abels hus, 8th floor

Geoff Nicholls (Department of Statistics, University of Oxford) and Idris Eckley (Mathematics and Statistics, Lancaster University) will both give a talk on September 17th, at 13:45 and 14:45, respectively, in the Seminar Room 819, Niels Henrik Abels hus, 8th floor.

Tid og sted: 14. sep. 2018 11:15 - 12:00, NHA 919
Tid og sted: 7. sep. 2018 11:15 - 12:00, NHA 919

Title: Taming nonlinear dynamics using Deep Reinforcement Learning

by: Jean Rabault, Miroslav Kuchta, Ulysse Réglade and Nicolas Cerardi

Abstract: Machine Learning (ML) methods are a promising way to perform optimal control. In a recent book ('Machine Learning Control - Taming Nonlinear Dynamics and Turbulence', Duriez et. al., 2017), several ML methods were presented as well as a couple of benchmarks. One particular benchmark is a small system of ODEs that present features, such as multimodality and cross-talks, that are representative of more complex systems found in Fluid Mechanics.

In this seminar, we present ongoing work about active control of this system of ODEs.

Tid og sted: 6. sep. 2018 10:15 - 12:00, Ole Johan Dahls hus
Tid og sted: 4. sep. 2018 14:15 - 15:15, Niels Henrik Abels hus, 8th floor

Paolo Vidoni (Department of Economics and Statistics, University of Udine) will give a talk on September 4th at 14:15 in the Seminar Room 819, Niels Henrik Abels hus, 8th floor.

Tid og sted: 29. aug. 2018 10:15 - 12:00, 1120 N.H.A.

The Mahowald invariant is a method for constructing nontrivial classes in the stable homotopy groups of spheres from lower dimensional classes. I will introduce this construction and recall Mahowald and Ravenel's computation of the Mahowald invariant of 2^i for all i . I'll then introduce motivic and equivariant analogs of the Mahowald invariant, outline the computation of the generalized Mahowald invariants of 2^i and \eta^i for all i , and discuss the relationship between these generalized computations and exotic periodicity in the equivariant and motivic stable homotopy groups of spheres.

Tid og sted: 24. aug. 2018 11:15 - 12:00, NHA B919
Tid og sted: 9. aug. 2018 11:15 - 12:00, NHA 919

Christophe Henry

Post doc at Observatoire de la Cote d'Azur, Laboratoire Lagrange

Tid og sted: 27. juni 2018 11:15 - 12:00, Seminar room 1020, Niels Henrik Abel's house
Tid og sted: 7. juni 2018 13:15 - 14:00, Seminar room "Hurricane"
Tid og sted: 6. juni 2018 09:15 - 16:30, Hotel Bristol

A seminar in the honour of Erik Bølviken at his 70’th birthday.

Tid og sted: 30. mai 2018 11:35 - 12:20, Seminar room "End of the Line"
Tid og sted: 30. mai 2018 11:00 - 11:30, Gates of Eden, Ullevål stadion (Sognsveien 77 B, 2nd floor)

Kostiantyn Ralchenko (Taras Shevchenko National University of Kyiv) gives a lecture with the title: Maximum likelihood estimation for drift parameter of Gaussian process.

Tid og sted: 30. mai 2018 10:30 - 11:00, Gates of Eden, Ullevål stadion (Sognsveien 77 B, 2nd floor)

Yuliia Mishura (Taras Shevchenko National University of Kyiv) gives a lecture with the title: Fractional Cox-Ingersoll-Ross process and its applications to financial markets.

Tid og sted: 9. mai 2018 11:15 - 12:00, Seminar room "End of the Line"
Tid og sted: 4. mai 2018 12:45 - 13:45, Gates of Eden, Sognsv. 77B
 Abstract: I will give a brief introduction to the Langlands program, using the language and theorems of representation theory to connect Galois groups to automorphic forms.
Tid og sted: 3. mai 2018 13:00 - 14:00, Hurricane, Ullevål

Kurusch Ebrahimi-Fard (NTNU) will give a talk with title: Moment-cumulant relations in noncommutative probability and shuffle-exponentials

Abstract: In this talk we consider monotone, free, and boolean moment-cumulant relations from the shuffle algebra viewpoint. Cumulants are described as infinitesimal characters over a particular combinatorial Hopf algebra, which is neither commutative nor cocommutative. As a result the moment-cumulant relations can be encoded in terms of shuffle and half-shuffle exponentials. These shuffle exponentials and the corresponding logarithms permit to express monotone, free, and boolean cumulants in terms of each other using the pre-Lie Magnus expansion. If time permits we will revisit additive convolution in monotone, free and boolean probability and related aspects. Based on joint work with F. Patras (CNRS).

Tid og sted: 2. mai 2018 14:15 - 16:00, Gates of Eden, Sognsveien 77 B

In this second talk I will prove the local slice theorem and give examples of applications, discuss compactness properties of instanton moduli spaces, and explain the definition and some properties of instanton homology.