Tidlegare gjesteforelesninger og seminarer - Side 41
I will report on work in progress on calculations of the motivic homotopy groups of MGL (the algebraic cobordism spectrum) over number fields. It is known that pi_{2n,n}(MGL) is the Lazard ring, and pi_{-n,-n}(MGL) is Milnor K-theory of the base field. We will calculate all of pi_{*,*}(MGL) with the slice spectral sequence (motivic Atiyah-Hirzebruch spectral sequence) over a number field. I will give a brief review of the the tools and sketch the main parts of the calculation: The input from motivic cohomology, the use of C_2-equivariant Betti realization and comparison with Hill-Hopkins-Ravenel to determine the differentials, and settle most of the hidden extensions.
In the past years there has been several publications on the association between acetaminophen during pregnancy and offspring ADHD symptoms. The aim of the webinar will be to present the recent study, discuss what it adds, and discuss what kind of future studies are needed.
by Dr. Dag Endresen, GBIF Node Manager for Norway at the Natural History Museum in Oslo.
Vasco Henriques, Postdoc, ITA
Nå arrangeres Arktisk Dag ved UiO igjen! Tema for dagen er "Opening the Arctic – Challenges and opportunities".
I will discuss the algebra structure of the E_2-term of the mod 2 Adams spectral sequence for tmf, given by the cohomology Ext_{A(2)}(F_2, F_2) of A(2). We (Bruner & Rognes) use Groebner bases to verify the presentation given by Iwai and Shimada, with 13 generators and 54 relations. Thereafter I will discuss the relationship between differentials and Steenrod operations in the Adams spectral sequence for E_\infty ring spectra.
Pawel Kasprzak (Warzaw) will give a talk with title " Quantum actions on discrete quantum spaces"
Abstract:
To any action of a compact quantum group on a von Neumann algebra which is a direct sum of factors we associate an equivalence relation corresponding to the partition of a space into orbits of the action. We show that in case all factors are finite-dimensional (i.e. when the action is on a discrete quantum space) the relation has finite orbits. We then apply this
i) to generalize the classical theory of Clifford, concerning the restrictions of representations to normal subgroups, to the framework of quantum subgroups of discrete quantum groups, itself extending the context of closed normal quantum subgroups of compact quantum groups; ii) to the context of idempotent states showing that the algebra of invariant elements is finite dimensional if and only if the corresponding state is normal. Joint work with K. De Commer, A. Skalski and P. Sołtan.
By Prof. Katriona Shea, Penn State, US.
William Coulton, Princeton
When and how surface structure determines the dynamics of partial wetting
I will discuss machine computations in a finite range, using Bruner's ext-program, of Ext over A, the mod 2 Steenrod algebra, and over A(2), the subalgebra of A generated by Sq^1, Sq^2 and Sq^4. These are the E_2-terms of the mod 2 Adams spectral sequences for S and tmf, respectively.
Sedimentation-diffusion equilibrium of Quincke rollers
Oscar Agertz, Researcher, Lund Observatory
By Prof. Ottar Bjørnstad, Penn State, US.
Please note the time change!
The Strategic Research Initiatives DIATECH and REALOMICS will present status and their plans for the future.
Erik Bedos (UiO) will give a talk with title "On Exel-Pardo algebras as Cuntz-Pimsner algebras"
Abstract:
Line Nybakk Akerholt, Head Librarian - Science Library
Nicolai Stammeier (Oslo) will give a talk with title: The inner structure of boundary quotients of right LCM semigroups
Abstract: In joint work with Roberto Conti, Stefano Rossi, and Valeriano Aiello, we use semidirect products built from algebraic dynamical systems to model right LCM semigroups to study various structural aspects in connection with a selection of distinguished subalgebras of the associated boundary quotients. Our two guiding examples are integral dynamics as considered in work of Barlak - Omland - Stammeier, and exact injective group endomorphisms of discrete abelian groups with finite cokernel as studied by Cuntz and Vershik.
By Erik Bonsdorff, professor of marine biology at Åbo Akademi University, Finland
Luc Blanchet, Directeur de Recherche au C.N.R.S., Institut d'Astrophysique de Paris