Konferanser og sommerskoler

The purpose of this workshop is to bring together communities in dynamical systems, harmonic analysis and operator algebras whose research relates to point sets in Euclidean space and general locally compact groups.

University of Oslo and University of Gothenburg invite to an informal workshop within machine learning with a focus on statistical aspects related to Machine Learning.

Phase tropical surfaces can appear as a limit of a 1-parameter family of smooth complex algebraic surfaces. A phase tropical surface admits a stratified fibration over a smooth tropical surface. We study the real structures compatible with this fibration and give a description in terms of tropical cohomology. As an application, we deduce combinatorial criteria for the type of a real structure of a phase tropical surface.

Phase tropical surfaces can appear as a limit of a 1-parameter family of smooth complex algebraic surfaces. A phase tropical surface admits a stratified fibration over a smooth tropical surface. We study the real structures compatible with this fibration and give a description in terms of tropical cohomology. As an application, we deduce combinatorial criteria for the type of a real structure of a phase tropical surface.

In 1962 Ehrhart proved that the number of lattice points in integer dilates of a lattice polytope is given by a polynomial — the Ehrhart polynomial of the polytope. Since then Ehrhart theory has developed into a very active area of research at the intersection of combinatorics, geometry and algebra.

The Ehrhart polynomial encodes important information about the polytope such as its volume and the dimension. An important tool to study Ehrhart polynomials is the h*-polynomial, a linear transform of the Ehrhart polynomial which is given by the numerator of the generating series. By a famous theorem of Stanley the coefficients of the h*-polynomial are always nonnegative integers. In this talk, we discuss generalizations of this result to weighted lattice point enumeration in rational polytopes where the weight function is given by a polynomial. In particular, we show that Stanley’s Nonnegativity Theorem continues to hold if the weight is a sum of products of linear forms that a nonnegative over the polytope. This is joint work with Esme Bajo, Robert Davis, Jesús De Loera, Alexey Garber, Sofía Garzón Mora and Josephine Yu.

In 1962 Ehrhart proved that the number of lattice points in integer dilates of a lattice polytope is given by a polynomial — the Ehrhart polynomial of the polytope. Since then Ehrhart theory has developed into a very active area of research at the intersection of combinatorics, geometry and algebra.

The Ehrhart polynomial encodes important information about the polytope such as its volume and the dimension. An important tool to study Ehrhart polynomials is the h*-polynomial, a linear transform of the Ehrhart polynomial which is given by the numerator of the generating series. By a famous theorem of Stanley the coefficients of the h*-polynomial are always nonnegative integers. In this talk, we discuss generalizations of this result to weighted lattice point enumeration in rational polytopes where the weight function is given by a polynomial. In particular, we show that Stanley’s Nonnegativity Theorem continues to hold if the weight is a sum of products of linear forms that a nonnegative over the polytope. This is joint work with Esme Bajo, Robert Davis, Jesús De Loera, Alexey Garber, Sofía Garzón Mora and Josephine Yu.

In this talk we define a new category of matroids, by working on matroid polytopes and rank preserving weak maps. This lets us introduce the concept of categorical valuativity for functors, which can be seen as a categorification of the ordinary valuativity for matroid invariants.

We also show that this new theory agrees with what we know about valuative polynomials: several known valuative polynomials can be seen as a Hilbert series of some graded vector space and we prove that these graded vector spaces let us define a valuative functor in the new sense. 

Lastly, we sketch how to categorify a Theorem by Ardila and Sanchez, which states that the convolution of two valuative invariants (respectively, valuative functors) is again valuative.

This is based on a joint ongoing project with Ben Elias, Dane Miyata and Nicholas Proudfoot.

In this talk we define a new category of matroids, by working on matroid polytopes and rank preserving weak maps. This lets us introduce the concept of categorical valuativity for functors, which can be seen as a categorification of the ordinary valuativity for matroid invariants.

We also show that this new theory agrees with what we know about valuative polynomials: several known valuative polynomials can be seen as a Hilbert series of some graded vector space and we prove that these graded vector spaces let us define a valuative functor in the new sense. 

Lastly, we sketch how to categorify a Theorem by Ardila and Sanchez, which states that the convolution of two valuative invariants (respectively, valuative functors) is again valuative.

This is based on a joint ongoing project with Ben Elias, Dane Miyata and Nicholas Proudfoot.

The workshop will bring together leading specialists in modeling roughness and long-range dependence in a cozy Nordic atmosphere in the center of Oslo close to the seafront.

Oslo Stability and Enumerative Geometry Workshop 2023

SCV conference 2023, remembering Berit Stensønes. 

We invite you to a two day seminar celebrating Nils Lid Hjort's significant and extensive contributions in statistics.

On November 21-23 the Integreat team and partners convened for the first-ever kick-off meeting at the historic Tøyen Hovedgård in Oslo. The event marked a crucial milestone for the Integreat community and served as an opportunity to articulate common goals, define the purpose of upcoming projects, and facilitate team building.

As we bid farewell to 2023 and welcome the first hints of winter, we invite you to take part in "The Winds of STORM" workshop!

Workshop at University of Oslo

30-31 October 2023, Oslo, Norway. 

The symposium is a follow-up of six highly successful previous DNVA-RSE Norway-Scotland Symposia. Topics of this year's symposium include: Water Waves and Internal Waves, and the widened scope to include the following multi- and inter-disciplinary marine topics: Hydrodynamic processes in the coastal ocean and fjords, Microbial processes, Robotics for observations in the ocean, Corals and plankton, and Arctic-related problems. 

The conference is an occasion to bring together researchers in the beautiful Hammamet to discuss on the recent developments in stochastics with applications to mathematical physics and finance.

An event dedicated to the memory of Habib Ouerdiane.