## Visiting address

Ullevål StadionSognsveien 77B

0855 OSLO

Norway

Time and place:
Apr. 10, 2015 -
Apr. 11, 2015,
The Norwegian Academy of Sciences and Letters

Time and place:
Apr. 8, 2015 2:15 PM - 3:00 PM,
NHA B735

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).

Time and place:
Mar. 26, 2015 2:15 PM - 4:00 PM,
B62, NH Abels hus

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

Modular curves V

Time and place:
Mar. 25, 2015 2:15 PM -
Mar. 23, 2015 4:00 PM,
VB, Auditorium 2

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

Time and place:
Mar. 25, 2015 1:00 PM - 3:00 PM,
"bikuben" - Kristine Bonnevies hus

Time and place:
Mar. 25, 2015 12:00 PM - 2:30 PM,
Nuklus - 2+3 in Kristine Bonnevies hus (Biology building)

Time and place:
Mar. 24, 2015 12:15 PM -
Mar. 23, 2015 2:00 PM,
VB, Auditorium 2

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

Time and place:
Mar. 23, 2015 12:15 PM - 2:00 PM,
VB, Auditorium 2

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

Time and place:
Mar. 19, 2015 2:15 PM - 4:00 PM,
B62, NH Abels hus

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

Modular curves IV

Time:
Mar. 17, 2015 2:15 PM

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

Time and place:
Mar. 12, 2015 2:15 PM - 4:00 PM,
B62, NH Abels hus

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

Modular curves III

Time and place:
Mar. 12, 2015 10:15 AM - 12:00 PM,
Ole Johan Dahls hus, møterommet i etasje 9

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

On the contingency of predicativism.

Time and place:
Mar. 11, 2015 2:15 PM - 4:00 PM,
NHA B71

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.

Time:
Mar. 10, 2015 2:15 PM

John Dagsvik ( Statistics Norway ) gives a seminar in room 107, 1st floor N.H. Abels House at 14:15 March 10th: How Does the Temperature Vary over Time? Evidence on the Stationary and Fractal Nature of Temperature Fluctuations

Time and place:
Mar. 5, 2015 2:15 PM - 4:00 PM,
B62, NH Abels hus

Johannes Kleppe, Høskolen i Buskerud og Vestfold, gives the Seminar in Algebra and Algebraic Geometry:

Modular curves II

Time and place:
Mar. 4, 2015 2:15 PM - 4:00 PM,
NHA B735

Bartosz K. Kwaśniewski (University of Southern Denmark, Odense) will talk on: Topological aperiodicity for product systems of C*-correspondences

Abstract:We introduce a semigroup of multivalued maps dual to a product system of $C^*$-correspondences over an Ore semigroup. Under a certain aperiodicity condition on the dual semigroup we obtain a uniqueness theorem and a simplicity criterion for the associated Cuntz-Pimsner algebra. These results generalize similar statements for crossed products by groups (R. J. Archbold, J. S. Spielberg) and Exel’s crossed products (R. Exel, A. Vershik). They also give interesting conditions for topological higher rank graphs, and apply to the new Cuntz $C^*$-algebra $\mathcal{Q}_\mathbb{N}$ arising from the `$ax+b$'-semigroup over natural numbers. (Based on joint work with Wojciech Szymański.)

Time and place:
Feb. 26, 2015 2:15 PM - 4:00 PM,
B62, NH Abels hus

Geir Ellingsrud, UiO, gives the Seminar in Algebra and Algebraic Geometry:

Modular curves I

Time and place:
Feb. 25, 2015 2:15 PM - 4:00 PM,
NHA B71

Adam P.W. Sørensen will talk on Nuclear dimension of UCT Kirchberg algebras

Abstract: Nuclear Dimension is a regularity property for C*-algebras that is based on the type of properties currently being taught in Topics in Operator Algebras. We will go over the definition and motivation and discuss known results.

Time:
Feb. 24, 2015 2:15 PM

Kasper Christensen ( Nofima, Ås and Aarhus university ) gives a seminar in room 107, 1st floor N.H. Abels House at 14:15 February 24th: Mining for new product ideas.

Time and place:
Feb. 18, 2015 2:15 PM - 3:15 PM,
NHA B735

Time and place:
Feb. 12, 2015 2:15 PM - 4:00 PM,
B62, NH Abels hus

Atanas Iliev, Seoul National University, gives the Seminar in Algebra and Algebraic Geometry:

Fano manifolds - old and new

Time and place:
Feb. 11, 2015 2:15 PM - 4:00 PM,
NHA B735

Makoto Yamashita, Ochanomizu University, will give a talk with title: Drinfeld center and representation theory for monoidal categories

Abstract: Motivated by the recently found relation between central completely positive multipliers and the spherical unitary representations of the Drinfeld double for discrete quantum groups, we construct and analyze the representations of fusion algebra of rigid C*-tensor category from the unitary half-braidings. Through the correspondence of Drinfeld center and the generalized Longo-Rehren construction in subfactor theory, these representations are also related to Popa’s theory of correspondences and subfactors. This talk is based on joint work with Sergey Neshveyev.

Time and place:
Feb. 10, 2015 2:15 PM,
Room 107, 1st floor N.H. Abels House

Håvard Rue ( Dept. of math., NTNU) gives a seminar in room 107, 1st floor N.H. Abels House at 14:15 February 10th: Penalising model component complexity: A principled practical approach to constructing priors

Time and place:
Feb. 5, 2015 1:00 PM - 3:00 PM,
Undervisningsrom 126 Niels Henrik Abels hus

Her er innledning

Time and place:
Feb. 3, 2015 2:15 PM,
rom 107, N.H. Abels hus

Helge Brunborg (Statistisk sentralbyrå) holder et seminar i rom 107, 1. etasje N.H. Abels Hus kl. 14:15 tirsdag 3. februar: Hva skjer med verdens befolkningsutvikling?