Events - Page 18

Time and place: Apr. 22, 2015 1:05 PM, Ø467

Carmelo Evoli, Universität Hamburg [slides]

At GeV-TeV energies the propagation of CRs in our Galaxy is diffusive. Current models of galactic propagation are based on a simplified approach for which diffusion is constant and isotropic. In fact, diffusion transport must be described as in-homogenous and anisotropic and experimental data have now reached an accuracy that allows to study such effects.  

In my talk, I will present some of the consequences of adopting realistic diffusion models for the propagation of galactic CRs, and I will show how these models allow a better understanding of local observations and diffusion emissions within an unified framework.

In the second part of my talk, I will focus on antiprotons as a tool to set constraints on DM models.  In particular, I will discuss the uncertainties associated to both standard astrophysical and DM originated antiprotons. I will show on which extent current antiproton data can place tight constraints on DM models, excluding some of those suggested in connection with indirect and direct searches.

Time and place: Apr. 17, 2015 3:15 PM4:00 PM, Seminar room (FV414)

Thomas Schuler, Andi Kaab (Department of Geosciences, UiO) and Anders Malthe-Sørenssen  (Department of Physics, UiO) will give a talk in relation to the EarthFlow project (a new cross-disciplinary Strategic Research Initiative), addressed to a broad audience.

Time and place: Apr. 15, 2015 1:05 PM, Ø467

Marco Cirelli, Saclay, France [slides]

The field of Dark Matter Indirect Detection is in a thriving but somewhat chaotic moment: quite a few hints of possible detection of signals of DM (over a large range of masses and, in general, inferred properties) are confronted with stringent constraints, often based on the same experiments that provide the possible hints. In turn, this spurs a lot of theoretical activity, aimed at phenomenologically analyzing the claims and, perhaps, at embedding them in wider model building. I will briefly review the current status of the searches, mention the most debated hints and sketch the general directions of the theory activity.

Time: Mar. 27, 2015 9:00 AM10:00 AM

Bjørn Vidar Johansen, leader of The Museum of University and Science  History at the University of Oslo, will guide us in the Observatory of the University of Oslo.

Time and place: Mar. 25, 2015 1:05 PM, Ø467

Daniele Gaggero, SISSA, Trieste, Italy  [slides]

In the first part of the talk, after a general introduction on the physics of cosmic rays (CRs), I present a detailed overview on recent results regarding modeling of CR propagation in the Galaxy and in the Heliosphere. In particular I focus on the necessity to go beyond the standard and simplified picture of uniform and homogeneous diffusion, showing that gamma-ray data point towards different propagation regimes in different regions of the Galaxy. I also sketch the impact of large-scale structure on CR observables. Concerning the propagation of the Heliosphere, I mention the necessity to consider a charge-dependent modulation scenario.

In the second part, I discuss several aspects of the recent claim of a gamma-ray excess in the Galactic center region, discussing in particular the interpretation in terms of Dark Matter, compared to other astrophysical interpretations. I will emphasize the interplay between the non-trivial aspects of CR propagation discussed in the first part and the understanding of the GC excess origin. In particular, I will show in detail how the knowledge of the CR transport parameters and solar modulation is crucial to investigate the compatibility with other channels (namely antiprotons) and to provide alternative astrophysical interpretations.

Time and place: Mar. 23, 2015 12:14 PM1:00 PM, PGP-CM seminar room, V414

Jacob Israelachvili, professor in chemical engineering at the University of California Santa Barbara, will give us an account on the history of the ideas, concepts and theories of intermolecular, inter-particle and inter-surface forces. Jacob Israelachvili is visiting PGP in connection with the installation of the Surface Forces Apparatus (SFA), which he has been leading the development of since the 1970s. He is also well known as the author of the book Intermolecular and Surface Forces

Time and place: Mar. 20, 2015 3:15 PM4:00 PM, Seminar room (FV414)

Talk in relation with the EarthFlow project, but addressed to a broad audience, by Marcin Dabrowski (PGP, UiO). 

Time and place: Mar. 19, 2015 12:15 PM1:00 PM, PGP-CM seminar room, V414

Kai Kristiansen, from the University of California Santa Barbara, will tell us of their results on electrochemical processes in pressure solution using the surface forces apparatus. 

Time and place: Mar. 11, 2015 1:05 PM, Ø467

Susanne Viefers, UiO

In recent years there has been substantial interest in the study of strongly correlated states of cold atoms, analogous to exotic states known from low-dimensional electron systems - one 'holy grail' being experimental realisation of quantum Hall-like states in atomic Bose condensates. In particular there have been many studies on the rotational properties of cold atom systems, as rotation is the conceptually simplest way of simulating a magnetic field for electrically neutral atoms. Even richer physics is expected in the case of two-species gases, such as mixtures of two types of bosonic atoms.

In this talk I will give an introduction to the field, followed by some recent results on the rotational properties of two-species Bose gases in the lowest Landau level. In particular we show that, contrary to expectations, trial wave functions of the composite fermion (CF) type, known from quantum Hall physics, give a very accurate description of this system. It is also shown how working only with a certain subset of possible CF candidate wave functions constitutes a major computational simplification without much loss of accuracy for the low-lying states. Finally I will briefly discuss some striking mathematical identities between seemingly different CF candidate states, of interest for a better understanding of the CF method in general.

Time and place: Mar. 6, 2015 3:15 PM4:00 PM, Seminar room (FV414)

Talk in relation with the EarthFlow project but addressed to a broad audience by Anja Røyne (PGP, UiO)

Time and place: Mar. 5, 2015 9:00 AMMar. 6, 2015 3:00 PM, PGP seminar room (FV414)

On March 5th to 6th, a workshop on volcano plumbing systems in sedimentary basins takes place at PGP.

Time and place: Mar. 4, 2015 12:15 PM1:15 PM, PGP seminar room (V414, Physics building)

Alain Zanella, lecturer at Université du Maine, will present his work on "Natural hydraulic fracturing in organic rich source rocks: field observations and physical modelling".

 

Time: Mar. 3, 2015 9:50 AM5:00 PM

Each year in spring, research institutes and universities around the world invite high-school students for a day-long programme to experience life at the forefront of basic research. These International Masterclasses give students the opportunity to be particle physicists for a day by analysing real data from the Large Hadron Collider, or LHC, at CERN. 

Time and place: Feb. 27, 2015 3:15 PM4:00 PM, Seminar room (FV414)

Talk given by Joachim Mathiesen, Niels Bohr Instituttet, Univ i København. Talk in relation with the EarthFlow project, but addressed to a broad audience

Time and place: Feb. 25, 2015 1:05 PM, Ø467

Abram Krislock, UiO

During Supersymmetry phenomenology research, involving simulations of the Large Hadron Collider experiments, a certain mistrust of data analysis using common histograms arose. Someone once said, "Change the bins and try the fit again..." A quest began to eliminate the bins entirely. After a recent study, it was clear that a deeper understanding of statistics was needed to complete this quest. A new probability calculus was discovered, leading to an interesting new data smoothing technique.

Time: Feb. 25, 2015 9:50 AM5:00 PM

Each year in spring, research institutes and universities around the world invite high-school students for a day-long programme to experience life at the forefront of basic research. These International Masterclasses give students the opportunity to be particle physicists for a day by analysing real data from the Large Hadron Collider, or LHC, at CERN. 

Time and place: Feb. 18, 2015 1:05 PM, FØ467

Carsten Lütken, UiO

The new states of matter and concomitant quantum critical phenomena revealed by the quantum Hall effect appear to be accompanied by an emergent modular symmetry. The extreme rigidity of this infinite symmetry makes it easy to falsify, but two decades of experiments have failed to do so, and the predicted location of quantum critical points is in accurate agreement with experiments.

The symmetry severely constrains the effective low energy physics of 1010 charges in two dirty dimensions. A toroidal σ­‐model gives a critical exponent that is in close agreement with numerical simulations. A double scaling law uncovered in the data suggests that the wave­‐function may be multi‐fractal.

The modular analysis can be extended to “relativistic” group IV materials like graphene, silicene, germanene and stanene, and where reliable data are available there appears to be agreement.

C.A. Lütken, Introduction to the role of modular symmetries in graphene and other 2-­‐dimensional materials, Contemp. Phys. (2014), http://dx.doi.org/10.1080/00107514.2014.949445

C.A. Lütken, G.G. Ross, Quantum critical Hall exponents, Phys. Lett. A 378 (2014) 262–265, http://dx.doi.org/10.1016/j.physleta.2013.11.001

Time and place: Feb. 13, 2015 3:15 PM4:00 PM, PGP seminar room (FV414)

Alix Young Vik and Lene Hystad Hove, from the Institute of Clinical Dentistry, Faculty of Dentistry, at UiO will present some of their reseach about the interaction between fluorides and the tooth enamel.

Time and place: Feb. 11, 2015 12:15 PM1:15 PM, PGP seminar room (V414, Physics building)

Anne Pluymakers, researcher at PGP, will present her PhD work on "Frictional and sealing behavior of simulated anhydrite fault gouge: Effects of CO2 and implications for fault stability and caprock integrity"

Time and place: Feb. 6, 2015 12:00 PM12:45 PM, Seminar (FV414)

Bjørn Vidar Johansen, leader of The Museum of University and Science History at the University of Oslo, will present us what was the initial plan for building the University of Oslo...a fascinating plan!

Bjørn V. Johansen is an art historian specializing in university architecture and university history. Between 1993 and 2004 he was employed by the Natural History Museum and the Cultural History Museum of UiO. From 2004 he has been head of the Museum of University History. His fields of work are architectural heritage and restoration, historical collections, research and outreach activities. He has also served as curator of the National Museum and project manager of the Norwegian Year of Cultural Heritage 2009.

 

Bjørn V. Johansen er kunsthistoriker med universitetsarkitektur og universitetshistorie som hovedområde. Fra 1993 til 2004 arbeidet han ved Naturhistorisk museum og kultur-historisk museum, UiO. I 2004 tiltrådte han som leder av Museum for universitets- og vitenskapshistorie (MUV). Arbeidsfelt er bygningshistorie og restaurering, gjenstands-forvaltning, forskning og ulike former for formidling. Utenfor UiO har han vært kurator ved Nasjonalmuseet og  prosjektleder ved Kulturminneåret 2009.

Time and place: Feb. 4, 2015 12:15 PM1:15 PM, PGP seminar room (V414, Physics building)

Marcel Moura, Ph.D student in the Condensed Matter Physics group, will present his work on "Two-phase flow in a quasi-2D porous medium: investigation of boundary effects in the measurement of pressure-saturation relationships"

Time and place: Jan. 30, 2015 3:15 PM4:00 PM, Seminar room (FV414)

Talk in relation with the EarthFlow project, but addressed to a broad audience, by Bjørn Jamtveit (PGP/UiO)

Time and place: Jan. 28, 2015 1:05 PM, FØ467

Pasquale Dario Serpico, LAPTh, Univ. de Savoy, CNRS

 

Despite its remarkable success, the Standard Model (SM) of particle physics does not address key facts revealed by cosmological and astrophysical observations. Until now, no signs of new physics have been discovered in laboratory experiments, leaving unclear what is the path chosen by Nature for the physics beyond the SM (BSM). I will discuss in this talk how indirect signals from Dark Matter (DM) might help us in this challenging "theoretical selection problem", with implications on foundational aspects of BSM physics. I will illustrate this point with possible DM interpretations of recent anomalies in multimessenger observations of energetic radiation of Galactic and extragalactic origin.
Time and place: Jan. 28, 2015 12:15 PM1:15 PM, PGP seminar room (V414, Physics building)

Janine Kavanagh, lecturer at University of Liverpool, will present her work on "Quantifying deformation and fluid dynamics in a developing model volcanic plumbing system"

Time and place: Jan. 23, 2015 3:15 PM4:00 PM, Seminar room - FV414

Jens Dyvik will present us the "Fellesverkstedet".

https://www.fablabs.io/fellesverkstedet

Jens Dyvik is a designer specialized in global collaboration and local manufacturing. He works with emotional connections between people and products, and aims to create services and products that help make those connections meaningful.

In 2013 he concluded a two year research world tour, where he worked at open collaborative workspaces on all corners of the world. He is currently applying this research into open design and personal manufacturing in Oslo, enabling him to make a living from an open and sharing design approach. He is also a co-founder of Fellesverkstedet, a super-FabLab in the making in Oslo.

Jens Dyvik er en designer spesialisert i globalt samarbeide og lokal produksjon. I april 2013 avsluttet han en toårig FabLab forskningreise hvor han jobbet på åpne digitale produksjonsverksteder jorden rundt. Han bruker denne kunnskapen om kortreist design, personlig produksjon og globalt samarbeide på sitt design studio i Oslo. Dette gjør han i stand til å leve av en åpen og delende tilnærming til design. Han er også co-founder av Fellesverkstedet, et åpent verksted for produksjon i Oslo.