Previous events - Page 122

Enrico Fermi and the birth of modern nonlinear physics

In the early fifties in Los Alamos E. Fermi in collaboration with J. Pasta and S. Ulam investigated a one dimensional chain of equal masses connected by a weakly nonlinear spring. The key question was related to the understanding of the phenomenon of conduction in solids; in particular they wanted to estimate the time needed to reach a statistical equilibrium state characterized by the equipartition of energy among the Fourier modes. They approached the problem numerically using the MANIAC I computer; however, the system did not thermailize and  they observed a recurrence to the initial state (this is known as the FPU-recurrence). This unexpected result has led to the development of the modern nonlinear physics (discovery of solitons and integrability). In this seminar, I will give an historical overview of the subject and present the different approaches that have been proposed in the last 60 years for explaining this paradox. Very recent results on the estimation of the time scale and on  the explanation of the mechanism of equipartition will also be discussed.

Doctoral candidate Mohammad Koochak Zadeh at the Department of Geosciences will give a trial lecture on the given topic: The application of rock physics in 4D seismic interpretation

In Part 2 we will delve into the worlds of derived and spectral algebraic

geometry. After reviewing some basic notions we will explain how motivic

homotopy theory can be extended to these settings. As far as time permits

we will then discuss applications to virtual fundamental classes, as well

as a new cohomology theory for commutative ring spectra, a brave new

analogue of Weibel's KH

In Part 2 we will delve into the worlds of derived and spectral algebraic

geometry. After reviewing some basic notions we will explain how motivic

homotopy theory can be extended to these settings. As far as time permits

we will then discuss applications to virtual fundamental classes, as well

as a new cohomology theory for commutative ring spectra, a brave new

analogue of Weibel's KH

Johanne Hope Rydsaa at the Department of Geosciences will be defending her dissertation: On biosphere-atmosphere interactions in a changing climate

Doctoral candidate Johanne Hope Rydsaa at the Department of Geosciences will give a trial lecture on the given topic: Biogenic Secondary Organic Aerosols (BSOA): sources, processes and climate impacts

UiO:Life Science will fund several «konvergensmiljø» – research groups with collaboration across conventional disciplinary boundaries. The application process starts with workshops with speed dating September 28 and 29.

UiO:Life Science will fund several «konvergensmiljø» – research groups with collaboration across conventional disciplinary boundaries. The application process starts with workshops with speed dating September 28 and 29.

Analysis on foreground cleaning methods for the CMB; Locating the residuals by correlation

We consider extensions of Morel-Voevodsky's motivic homotopy theory to the

settings of derived and spectral algebraic geometry. Part I will be a

review of the language of infinity-categories and the setup of

Morel-Voevodsky homotopy theory in this language. As an example we will

sketch an infinity-categorical proof of the representability of Weibel's

homotopy invariant K-theory in the motivic homotopy category.

Welcome to the GeoHyd Lunch Seminar on Monday Sept. 26th @ 12:15 in aud. 3 in the ZEB building (CEED-auditorium).

Numerical methods for stochastic conservation laws

Nick Kaiser, IfA, Hawai University

Experimental investigation of linear stability mechanisms in stratified gas-liquid pipe flow

The evolution of interfacial waves on a stratified air water pipe flow is investigated experimentally. An oscillating plate introduced controlled perturbations at the inlet of the pipe. High speed cameras captured the evolution of these perturbations along the pipe by means of a phase-locked shadowgraphy technique. Thereby, it was possible to measure the temporal and the spatial evolution of the disturbances introduced in the flow. Particle image velocimetry was performed further downstream in order to evaluate changes in the base flow. 

A relatively large data bank has been gathered with varying air and water flow rates as well as varying amplitudes and frequencies of the inlet perturbations. Some preliminary results contain a qualitative assessment of linear vs. non-linear regimes and momentum transfer into the water layer.

«Planeter fra innerst til ytterst». Det er temaet for CEEDs bod under årets forskningstorg på Universitetsplassen. Det årlige arrangementet som foregår under Forskningsdagene, har blitt en svært populær arena for å kunne presentere seg for allmennheten, og særlig for barn og unge. Dette er en ypperlig mulighet til å ta med barn og familie for å bli nysgjerrige, og lære!

Se mer info om arrangementet på Forskningstorgets egne hjemmesider

Text in English

Professor Eric Priest, St Andrews University, Scotland:

Our Dynamic Sun

Yuan Wang (Utah), gives the Seminar in Algebra and Algebraic Geometry:

"On the characterization of abelian varieties for log pairs in zero and positive characteristic"

Eric Priest, University of St.Andrews

Håvard Kvamme (UiO, Dept. of mathematics) will give a seminar in the lunch area, 8th floor Niels Henrik Abels hus at 14:15.

We will discuss the motivic May spectral sequence and demonstrate how to  use it to identify Massey products in the motivic Adams spectral sequence.  We will then investigate what is known about the motivic homotopy groups  of the eta-local sphere over the complex numbers and discuss how these  calculations may work over other base fields.  

Massive neutrinos and spherical collapse in ΛCDM and DGP gravity

Jack Carlyle, ITA, Postdoc

Welcome to the GeoHyd Lunch Seminar on Friday Sept. 16th @ 11:00 in aud. 1 in the Geology building.