Tidligere arrangementer - Side 3
The AtLAST conference will be held in-person in Mainz, Germany, from 21 to 24 May 2024.
Vi i prosjektet ?Sakkyndiges Arbeid som Bevis i Barnevernssaker (SABB)? (Experts? reports as evidence in child protection cases) er glade for ? kunne arrangere ?rets konferanse den 7. mai hvor vi setter s?kelyset p? barna og den private part. Her m?tes praktikere fra feltet, byr?krater, forskere og ikke minst brukere av tjenestene.
Konferansen er for deg som er opptatt av ? beskytte samfunnet, infrastrukturen og mennesker mot de stadig t?ffere klimautfordringene.
A two-day conference at the University of Oslo, on the publication of the anthology The Poverty of Anti-realism: Critical Perspectives on Postmodernist Philosophy of History.
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.
International Conference
Join us for the first NoRMAS meeting aimed at fostering collaboration and advancing research in the field of astronomy at long wavelengths, i.e infrared, (sub)millimeter and radio.
Welcome to the first Norwegian Planetary Health Alliance conference.
Welcome to our dScience lunch seminar in the Science Library, with Trude Storelvmo from the Department of Geosciences.
The Green Office celebrates its first year, and we invite you to join the birthday celebration!
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.
Det ?rlige m?tepunktet for alle som arbeider med formidling og utstillinger p? museum. ?rets tema: Relevans.
The Cultural Heritage Day is a day for dialogue and inspiration for everyone who studies and works with cultural heritage.
Kulturarvsdagen er en dag for dialog og til inspirasjon for alle som studerer og arbeider med kulturarv og kulturminner.
Do you want to learn more about sustainability work at UiO? Maybe you have a great idea for how to make UiO greener? Or possibly you have THE idea that will save us from the climate crisis? Then sign up for the Green Office’s Sustainathon!
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.
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.
Positroids are a class of matroids that were introduced by Postnikov in 2006 that index a certain stratification of the totally non-negative Grassmannian. These matroids are famously in bijection with a “zoo” of combinatorial objects including Grassmann necklaces and plabic graphs. We introduce a new family of positroids called rook matroids that arise from restricted rook placements on a skew shaped board and discuss it in terms of this zoo. We highlight the transversal structure of rook matroids and the slightly mysterious relationship they share with lattice path matroids. This is joint work with Per Alexandersson and ongoing work with Irem Portakal and Akiyoshi Tsuchiya.
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.