Tidligere arrangementer - Side 30

Given a knot K in the 3-sphere, we use Heegaard Floer correction terms to give lower bounds on the first Betti number of (orientable and non-orientable) surfaces in the 4-ball with boundary K. An amusing feature of the non-orientable bound is its superadditivity with respect to connected sums. This is joint work with Marco Marengon. If time permits, I will discuss relations with deformations of singularities of curves (joint work with József Bodnár and Daniele Celoria). 

Nacira Agram (University of Oslo) gives a lecture with the title: A Hida-Malliavin white noise calculus approach to optimal control

Roxana Dumitrescu (King’s College, London) gives a lecture with the title: Game options in an imperfect market with default

Perfeksjon fra bønne til kopp

Hvordan jobber Tim Wendelboe i sin jakt på den perfekte kopp med kaffe?

Tim er både kaffebonde, kaffebrenner og barista og vil gi deg et lite innblikk i alt arbeidet som ligger bak hver kopp kaffe som serveres i hans kaffebar på Grünerløkka.

Nicola Lunardon (Department of Economics, Management and Statistics, University of Milano-Bicocca) will give a seminar in the lunch area, 8th floor Niels Henrik Abels hus at 14:15.

Paul Krühner (TU Wien) gives a lecture with the title: On the Brownian limit order book dynamics

Florentina Paraschiv (Norges teknisk-naturvitenskapelige universitet) gives a lecture with the title: Estimation and Application of Fully Parametric Multifactor Quantile Regression with Dynamic Coefficients

In the 80's Bökstedt introduced THH(A), the Topological Hochschild homology of a ring A, and a trace map from algebraic K-theory of A to THH(A). This trace map, along with the circle action on THH, have since been used extensively to make calculations of algebraic K-theory. When the ring A has an anti-involution Hesselholt and Madsen have promoted the spectrum K(A) to a genuine Z/2-spectrum whose fixed points is the K-theory of Hermitian forms over A. They also introduced Real topological Hochschild homology THR(A), which is a genuine equivariant refinement of THH, and Dotto constructed an equivariant refinement of Bökstedt's trace map. I will report on recent joint work with Dotto, Patchkoria and Reeh on models for the spectrum THR(A) and calculations of its RO(Z/2)-graded homotopy groups. 

Adam Sørensen (Oslo) will give a talk with title: Overlapping qubits

Abstract: I will discuss the paper "Overlapping Qubits" by Chao, Reichardt, Sutherland, and Vidick (arXiv:1701.01062 - category: Quantum Physics!). Qubits are the bits of quantum computing. In the paper the authors take the point of view that a qubit mathematically is described by a pair of anticommuting reflections on a finite dimensional Hilbert space. Two qubits are independent if their defining operators commute. The central point of the paper is that when performing observations we should not expect two qubits to be exactly independent, rather we should expect them to be almost independent, i.e. the norms of the commutators should be small. This naturally leads to questions about almost commuting matrices, which is why I care. I will attempt to explain how questions of almost commuting matrices come up, and how the physicists answer them.  

Large Eddy Simulation of the interaction of water waves with turbulent air flow

Youssef Ouknine (Cadi Ayyad University, Marrakesh, Morocco) gives a lecture with the title: Optimal stopping with f-expectations: the irregular case.

Khalifa Essebaly (Cadi Ayyad University, Marrakesh, Morocco) gives a lecture with the title: Optimal rates for parameter estimation of stationary Gaussian processes.

Lan Zhang (University of Illinois at Chicago, Department of Finance) will give a seminar in the lunch area, 8th floor Niels Henrik Abels hus at 14:15. 

Riccardo De Bin (Department of Mathematics, University of Oslo) will give a seminar in the lunch area, 8th floor Niels Henrik Abels hus at 14:15.

The classical s-cobordism theorem classifies completely h-cobordisms from a fixed manifold, but it does not tell us much about the relationship between the two ends. In the talk I will present some old and new results about this. I will also discuss how this relates to a seemingly different problem: what can we say abobut two compact manifolds M and N if we know that MxR and NxR are diffeomorphic? This is joint work with Slawomir Kwasik, Tulane, and Jean-Claude Hausmann, Geneva.

I will survey the connection between the space H(M) of h-cobordisms on a given manifold M, several categories of spaces containing M, Waldhausens algebraic K-theory A(M), and the algebraic K-theory of the suspension ring spectrum S[?M] of the loop space of M. The results extend the h-cobordism theorem of Smale and the s-cobordism theorem of Barden, Mazur and Stallings to a parametrized h-cobordism theorem, valid in a stable range established by Igusa, first discussed by Hatcher and finally proved and published by Waldhausen, Jahren and myself.

Elizabeth Gillaspy, p.t. Münster (Germany) will give a talk with title "Wavelets and spectral triples for higher-rank graphs"  

Erik Bølviken (University of Oslo) gives a lecture with the title: Where models meet reality - The Solvency II regulation of  European insurance