NEWS

Internship Report in Statistical Physics

20 December 2011 Thsesis Defence

Nordita interns in statistical and biological physics Stefano Bo, Christian Karlewski (1st and 2nd from left) and Emma Ross (2nd from right) and their supervisors Ralf Eichhorn (center) and Erik Aurell (right).

Christian Karlewski from the University of Bielefeld has successfully concluded his internship at Nordita this fall with an internship report on "Numerical Studies of Optimal Protocols in Stochastic Thermodynamics". Christian's supervisor has been assistant professor Ralf Eichorn.

Congratulations to Nordita PhD-students

9 December 2011 Grants

Jörn Warnecke was awarded a travel grant from the Jubilee Donation of the K & A Wallenberg Foundation. He received 13 000 SEK to travel to La Palma and use the Swedish Solar Telescope (SST) to observe magnetic flux emergence and sunspots formation. This will be in cooperation with the Solar Physics Institute in Stockholm and Professor Göran Scharmer.

Fabio Del Sordo received a travel grant from the High Performance Computing-EUROPA2 initiative to visit Professor Alfio Bonanno at the National Institute for Astrophysics (INAF) in the Catania Astronomical Observatory for about 2 months to work on the study of chiral symmetry breaking from the Tayler instability and to perform computations at the local center.

Visit of Vice Chancellor of Stockholm University

9 November 2011 Visitors

On 9 November, Nordita had the pleasure of welcoming the Vice Chancellor of Stockholm University, Professor Kåre Bremer and his delegation consisting of pro-Vice Chancellor Lena Gerholm, the of Head of the Science Faculty Office, Åsa Borin, the Dean of the Faculty of Science, Professor Stefan Nordlund, and the Chairperson of the Mathematics and Physics Section, Professor Anders Karlhede. They met with Nordita's faculty and other members of staff. The delegation expressed delight in seeing the successful development of Nordita in Stockholm.

New Postdoctoral Fellows

14 October 2011 New Staff

Three new postdoctoral fellows arrived at Nordita in October.

Nordita Fellow Dr. Dmitri Bykov received his PhD from Trinity College Dublin in 2011. His research interests include spin chains, sigma models, gauge theory and string theory.

Post-doctoral fellow Dr. Ville Keränen received his PhD from the University of Helsinki in 2011. He is working on the use of the AdS/CFT duality to address questions in quantum field theory. His fellowship at Nordita is supported by a grant from the Icelandic Research Fund.

Nordita Fellow Dr. Dmytro Volin received his PhD from Univesité Paris-Sud XI, Orsay in 2009 and was a postdoc at the Pennsylvania State University before joining Nordita. His research interests include strongly coupled gauge theories and exactly solvable models, with particular focus on integrability in the AdS/CFT correspondence.

Alexander Balatsky to Join Nordita

14 October 2011 New Staff

Professor Alexander Balatsky will be joining Nordita in August 2012. His field of research is theoretical condensed matter physics where he has made a number of seminal contributions. His recent work has mainly been in strongly correlated materials, unconventional superconductivity, and biomolecular electronics.

Professor Balatsky received his PhD in 1987 at the Landau Institute for Theoretical Physics and Moscow Physical Technical Institute in Moscow.

He comes to Nordita from Los Alamos National Laboratory and has previously held positions at the Landau Institute and the University of Illinois at Urbana Champaign.

Tage Erlander Guest Professorship to Nordita

14 October 2011 New Staff

John S. Wettlaufer, the A.M. Bateman Professor at Yale University, and currently a Wenner-Gren visiting professor at Nordita, was awarded the Tage Erlander Guest Professorship 2012. A condensed matter theorist, John's expertise lies in, among other things, surface and size effects in melting and freezing, pattern formation and stability of moving boundaries, applied mathematics and fluid dynamics, and the statistical physics of soft matter. His work has implications in astrophysics, biophysics and geophysics.

The holder of the chair is appointed by invitation from the Swedish Research Council. Since its inception, this prestigious award has been given to accomplished scientists covering a broad range of topics including mathematics, signal processing, applied physics, theoretical biology, nuclear physics, and chemistry. Nobel Laureates, Fields Medalists and members of many National Academies of Science are included in the list of past Erlander Professors.

John's term will be spent at Nordita where with collaborators and students he plans to study the surface phase transitions underlying planetary accretion, the statistical physics of rapid climate change, and lattice Boltzmann methods for electromagnetism and fluid dynamics.

Turbulent Progress

3 October 2011 Publications

Members of the ERC-supported AstroDyn project were excited to report on what they call a negative effective magnetic pressure instability (or NEMPI for short). During the last year they did already verify that on large enough length scales covering many turbulent eddies, a modestly strong magnetic field can suppress turbulence, lowering therefore the turbulence pressure locally. In spite of the added magnetic pressure, the total effective pressure can still get reduced.   Read more

Christos Tsagas spending his sabbatical at Nordita

26 September 2011 New Staff

Nordita is happy to host Christos Tsagas for over 2 months. Christos has been an Assistant Professor at the University of Thessaloniki in Greece since the autumn of 2005. Previously, he has been a postdoctoral researcher at Portsmouth (ICG), Cape Town (RCG) and Cambridge (DAMTP). He received his PhD from the University of Sussex in 1998, where he worked under the supervision of Professor John Barrow.

Christos is a theorist with research interests in the interface between Relativistic Cosmology and Relativistic Astrophysics and he is the author/coauthor of approximately fifty scientific articles, reviews and conference proceedings. His main expertise is in the area of cosmological magnetic fields and the large-scale structure of the universe. His work on the interaction between electromagnetism and spacetime geometry has attracted the attention of the wider scientific community, with related news pieces appearing in magazines and newspapers worldwide.

During his visit between mid September and early December 2011, Christos will be working with Axel Brandenburg and his research group on a project studying the interaction between gravitational waves and electromagnetic fields.

PhD defense: Tobias Zingg

2 September 2011 Thesis Defence

Nordita PhD student Tobias Zingg successfully defended his PhD thesis "Holographic Models for Condensed Matter" at the University of Iceland on September 2. His PhD advisor is Nordita Director Lárus Thorlacius.

Tobias will be staying on at Nordita as a post-doctoral fellow, supported by a grant from the Icelandic Research Fund, until summer 2012.

First Nordita Stockholm Licenciate Thesis Defences

11 February 2011 Thesis Defence

Nordita PhD students Fabio Del Sordo and Simon Candelaresi have successfully defended their licentiate theses, "Generation of Magnetic Fields on Galactic Scales" and "Magnetic Helicity Fluxes and their Effects in Dynamo Theory" (PDF-files).

Visitor to Nordita and KTH Mathematics Dept.

24 January 2011 Visitors

Maciej Trzetrzelewski from the Jagiellonian University in Krakow is currently visiting Nordita. His chief interests are in membrane theory.

VR Grant to Nordita Fellow Annica Black-Schaffer

7 December 2010 Grants

Nordita Fellow Annica Black-Schaffer has been awarded a 4 year grant from Vetenskapsrådet (the Swedish Research Council) to fund a forskarassistenttjänst (assistant professor) position in the Materials Theory group at Uppsala University. The proposal title is "Magnetism and superconductivity in two unique materials: graphene and high-Tc superconductors". She will take up her new position in Summer 2011.

New Condensed Matter PhD Student Position

7 December 2010 Grants

Nordita Assistant Professor Eddy Ardonne received a grant from Vetenskapsrådet to appoint a PhD student. The title of the project is "Topological phases of matter: characterization and stability". The PhD position will be advertised in early 2011.

Chris Pethick to Receive the 2011 Hans Bethe Prize

7 December 2010 Awards

Nordita Professor Emeritus Chris Pethick will receive the 2011 Hans Bethe Prize from the American Physical Society,

“for fundamental contributions to the understanding of nuclear matter at very high densities, the structure of neutron stars, their cooling, and the related neutrino processes and astrophysical phenomena.”

The Bethe Prize will be presented at a special ceremonial session of the APS April 2011 meeting in Anaheim, California, April 30-May 3, 2011.

Nordita Research Highlighted by Journal of Physics

18 February 2010 Publications

A figure taken from the article Quantum fluctuations in the mazer (J. Phys. B 42, 2009, 044015) by Nordita fellow Jonas Larson was chosen to be the cover of the 2009 Highlight brochure for Journal of Physics B: Atomic, Molecular and optical Physics. (For the interested; the figure shows the time evolution of an atomic wavepacket bunching against a quantized cavity field.)

Condensed Matter PhD Student Position Grant

18 February 2010 Grants

Nordita condensed matter physicists Jani-Petri Martikainen and Jonas Larson have been awarded a grant (projektbidrag) by the Swedish Research Council (Vetenskapsrådet). The grant is for 4 years and covers the expenses for one PhD student. Information about the position can be found at http://www.fysik.su.se/om/tjanster/.

Second Price in FQXi Annual Essay Contest

20 January 2010 Awards

The essay "At the Frontier of Knowledge" by Sabine Hossenfelder, assistant professor at Nordita (Stockholm), is awarded a shared second prize in the The Foundational Questions Institute (FQXi) annual Essay Contest on the question "What is Ultimately Possible in Physics?".

State Prize of Ukraine to Aleksandr Zheltukin

7 January 2010 Awards

Aleksandr Zheltukin, visiting professor at Nordita (Stockholm), is one of the recipients of the State Prize of Ukraine in Science and Technology for 2009. The prize was awarded Dmitrij Volkov and his collaborators at the KIPT in Kharkov for "the discovery and development of principles of supersymmetry and supergravity and their application to the construction of a unified theory of fundamental interactions of elementary particles".

ERC Advanced Grant for Astrophysical Dynamos

18 September 2008 Grants

An ERC Advanced Grant was awarded to Prof. Axel Brandenburg, Nordita. The project Astrophysical Dynamos is funded by the European Research Council with €2220000 during a five year period.

New Photos from Nordita Workshops

22 August 2008 Reports from Meetings

We have added to our photo gallery some action-packed photos from the recent program TeV scale physics and dark matter and conference Conformal field theory approach to quantum Hall physics. Enjoy!

Astrophysics Workshop

7 January 2008 Nordic Events

The high energy astrophysics workshop "Cool discs, hot flows: Varying faces of accreting compact objects" will be held in Funäsdalen, in the Swedish Mountains, 25-29 March 2008.

Lars Onsager Prize Awarded to Chris Pethick

5 October 2007 Awards

Chris Pethick of Nordita (Copenhagen) has been awarded the Lars Onsager Prize for 2008, "for fundamental applications of statistical physics to quantum fluids, including Fermi liquid theory and ground-state properties of dilute quantum gases, and for bringing a conceptual unity to these areas.".

Chris shares the prize with Gordon Baym (University of Illinois and a former Nordita adjunct professor) and Tin-Lun Ho (Ohio State, and also a former postdoc at Nordita). The Lars Onsager Prize is awarded by APS, the American Physical Society. There is a list of earlier recipients.

Pencil Code Meeting 2007

3 October 2007 Reports from Meetings

The full report (PDF file) from the meeting is now available, as are videos from meetings.

Inflation Assisted by Heterotic Axions

10 February 2007 Publications

It is widely belived that our Universe passed through a phase of exponential expansion called cosmic inflation shortly after the Big-bang. There is growing observational evidence for inflation but the detailed mechanism responsible for inflation is, however, not known. In a recent paper, "Inflation Assisted by Heterotic Axions", Dr. Martin Olsson at Nordita in Stockholm has suggested a specific string theory setting for explicitly realizing one of the proposed models for inflation, the so-called N-flation proposal. N-flation is, in turn, a special case of assisted inflation.

In this model inflation is driven by a large number of compact scalars called axions. The axions arise when the Kalb-Ramond field of heterotic string theory is compactified on a six dimenional manifold. In his paper, Olsson shows that the axions in weakly coupled heterotic string theory under some assumptions can drive inflation in such a way that the observed temperature fluctuations in the cosmic microwave background are correctly reproduced.

Nordita News

Next AlbaNova/Nordita Colloquium

Thursday, 8 March 2012

15:15      Oskar Klein Auditorium (FR4, AlbaNova Main Building)
COLLOQUIUM: The Linné excellence center in Advanced Optics and Photonics -- Who, what, and why?
Gunnar Björk  (KTH, AlbaNova)

Theoretical Physics Seminars

There are no events in theoretical physics scheduled for today.

Taken from the AlbaNova Agenda

See also list of all regular theory seminars at AlbaNova

Open Positions

Postdoc on Turbulence in Polymer Solutions 2012
Deadline: 31 March 2012

From the Preprint Archive

On Hydromagnetic Stresses in Weakly Magnetized Stellar Boundary Layers

by Martin E. Pessah and Chi-kwan Chan

We examine the generation of hydromagnetic stresses and energy density in the boundary layer around a weakly magnetized star in the shearing-sheet approximation. This region, where the angular frequency is expected to increases with radius, is stable against the magnetorotational instability. We provide analytic solutions for the long-term evolution of shearing MHD waves, which exhibit non-trivial dynamics. Even though their associated stresses oscillate around zero, their energy density can be amplified significantly. This is consistent with the findings of numerical simulations of MHD boundary layers and suggest that their detailed structure could differ appreciably from those derived within the standard framework of turbulent viscosity.

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11 Feb 2012