Friday, September 8, 2006, 15:30 in 330 Allen

High-precision experiments with cooled and trapped ions

Dr. Klaus Blaum
Mainz University

Accumulation, storing and cooling techniques play an increasingly important role in many areas of science. This is reflected by the awards of Nobel prizes within the last two decades to ten pioneers of particle, ion, or atom cooling. While in the beginning, storage of charged particles in ion traps was motivated purely by basic research, nowadays they play an important role in nuclear and atomic precision experiments. At GSI Darmstadt and at the University of Mainz (Germany) quite a number of novel trap instruments were and are being developed, or further optimized, such as Penning trap mass spectrometers of very high resolving power and accuracy and set-ups for QED and CPT tests, the determination of fundamental constants, and bound-state g- factor measurements in hydrogen- and lithium-like highly-charged ions [1]. The most important recent results with cooled and trapped ions in the field of high-precision mass spectrometry on short-lived nuclides and g-factor measurements on highly- charged ions will be presented and possible future techniques and applications discussed.
[1] K. Blaum, Phys. Rep. 425, 1-78 (2006)

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WINNIPEG INSTITUTE FOR THEORETICAL PHYSICS
The Road to Relativity

Dr. Jeff Williams
Department of Mathematics & Computer Science
Brandon University

Following his 1905 discovery of Special Relativity, Einstein began work on his General Relativity (GR), which was intended to explain gravity. By 1912, the pieces were in place and Einstein knew enough to complete GR by writing down the gravitational field equations. Yet his progress stopped abruptly and, for the next three years, Einstein tried several alternative approaches, repeatedly changing his mind. Then suddenly, in 1915, Einstein returned to his original idea and presented his equations.
What had been the difficulty that had prevented progress from 1912 to 1915? and how had Einstein resolved it?

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Time-Resolved Spectroscopy of Solid Surfaces Using Femtosecond XUV Light

Dr. Guido Saathoff
JILA, Boulder, Colorado

The generation of femtosecond laser pulses has revolutionized experimental physics and chemistry in that it allows the investigation of a plethora of relevant ultrafast processes like vibrations and rotations in molecules and surface-adsorbate systems directly in the time domain. The vast majority of these experiments employ pump-probe geometries in which a short pump pulse excites the dynamics of interest and a second pulse probes the evolution of these dynamics at different time delays with respect to the pump pulse. More recently the development of high-harmonic generation (HHG) has extended these techniques in two respects. First, it provides coherent light pulses in the extreme ultraviolet to soft x-ray wavelength range, where all materials exhibit numerous resonances. Secondly, the HHG light pulses have shown to be extremely short. Pulse durations down to the sub-femtosecond regime have been demonstrated and, in combination with the laser-assisted photoelectric effect, given access to electronic processes in atoms that occur on this time scale. In recent experiments, we have demonstrated that the physics of the laser-assisted photoelectric effect can also be extended to solid-state systems. In this talk, I will give an overview of the status and possible future developments of ultrafast spectroscopy, with special emphasis on solids where complex, correlated electron dynamics are expected.

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WINNIPEG INSTITUTE FOR THEORETICAL PHYSICS
Geometric Phases in Quantum Optics

Dr. Karl-Peter Marzlin
Institute for Quantum Information Science
University of Calgary

Slow Light and Colliding Photons: Quantum Optics and Quantum Information with Light

Dr. Karl-Peter Marzlin
Institute for Quantum Information Science
University of Calgary

During the last decade immense progress has been made in manipulating classical light beams and individual photons, thus creating the opportunity for new applications in quantum information processing. I will give an overview of some of the most remarkable achievements and prospects: slowing down light to a few m/s, storing and retrieving light and photons, and nonlinear optics at very low intensity levels (can we get two photons to interact with each other?).

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Thursday, October 12, 2006 at 15:30 in 330 Allen

WINNIPEG INSTITUTE FOR THEORETICAL PHYSICS

Calculations in Real Time Statistical Field Theory

Dr. Todd Fugleberg
Department of Mathematics & Computer Science
Brandon University

In this talk I will discuss a Mathematica program we have written which calculates the integrand corresponding to any amplitude in the closed-time-path formulation of real time statistical field theory. The program is designed so that it can be used by someone with no previous experience with Mathematica. It performs the contractions over the tensor indices that appear in real time statistical field theory and gives the result in the 1-2, Keldysh or RA basis. I will also discuss the application of this program to the analysis of 3, 4 and 5 point Ward identities in finite temperature QED.

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Friday, October 13, 2006 at 15:00 in 519 Allen

Graduate Student Colloquium

Graduate students from the UoM Department of Physics & Astronomy present their research work in brief presentations. All members of the department are strongly encouraged to attend this event! Pizza and refreshments will be served.

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Thursday, October 19, 2006 at 15:30 in 330 Allen

WINNIPEG INSTITUTE FOR THEORETICAL PHYSICS

Bose-Einstein Condensates and Thermal Field Theory


Dr. Randy Kobes
Department of Physics
University of Winnipeg

A homogeneous non-ideal Bose gas in equilibrium at non-zero temperature below the critical temperature is considered in the framework of thermal field theory. Quantum corrections up to the second order calculated, which are shown to be crucial in obtaining the correct behavior in thermodynamic quantities such as the specific heat.

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Thursday, October 26, 2006 at 15:30 in 330 Allen

Black Holes: The Simplest and Most Complex Objects in the Universe

Dr. Gabor Kunstatter
Department of Physics
University of Winnipeg

After a brief historical introduction, I will explain why black holes are, from a geometrical point of view, virtually structureless. I will then review the evidence that black holes behave much like thermodynamic systems with both temperature and entropy. This thermodynamic behaviour suggests that black holes contain a huge number of hidden microstates which may provide clues about the underlying theory of quantum gravity. Finally, I will give an overview of the modern context for these issues. In particular, I will describe recent attempts to extract information about quantum gravity from the semi-classical properties of black holes, and time permitting, I will explain why black holes may also be telling us something fundamental about information theory.

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Friday, October 27, 2006 at 15:30 in 330 Allen

Transport phenomena in fibrous and biomedical materials: Stochastic modeling and simulation

Dr. Wen Zhong
Department of Textile Sciences & Department of Medical Microbiology
University of Manitoba

Fluid transport is one of the most frequently observed phenomena in the processing and end uses of fibrous materials, including wicking and wetting, filtration and separation in geotextiles or other fibrous filters, and protective textiles against both aqueous and airborne hazard or pathogen. Fibrous materials have unique soft surfaces and complex structures that are characterized by anisotropy and heterogeneity, and have multi-scale pore distributions from intra-fiber to inter-fiber spaces. This multi-scale effect is even more pronounced in micro/nano-fibrous materials. Similar effect occurs in the various transport processes through biomembranes of complex structures.  The presented work will focus on multi-scale approaches to bridge the gap between our knowledge of the macro transport behavior of fibrous materials, and our knowledge of the interaction among micro constituents of materials.

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Friday, November 3, 2006 at 15:30 in 330 Allen

Joint Department of Physics & Astronomy and Winnipeg Institute for Theoretical Physics Colloquium

Quantum Mechanics and Phase Space

Dr. Mikhail Karasev
Moscow Institute of Electronics and Mathematics, Russia

We discuss the fundamental role of phase geometry in the works of Planck (1913), Sommerfeld (1915) and Heisenberg (1925) which have generated the modern quantum mechanics.

Then we consider Peierl’s (1933) ideas on a geometric interpretation of magnetic fields in the quantum framework.  We explain how magnetic phase geometry can influence the configuration space making it a quantum space (the von Klitzing experiment).

We also discuss how the simplest scalar light waves in fibre optics can carry non- trivial “quantum” properties similar to spin (whose phase space is the sphere).  This leads one to an unusual opportunity to quantize the configuration coordinates.

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Joint Department Colloquium/WITP Seminar
Is Equilibrium a Useful Concept in Physics?

Dr. D.A. Lavis
Department of Mathematics
King's College
Strand, London, UK

There are three levels of description in classical statistical mechanics, the microscopic/dynamic, the macroscopic/statistical and the thermodynamic. At one end there is a well-used concept of equilibrium in thermodynamics and at the other dynamic equilibrium does not exist in measure-preserving reversible dynamic systems. Statistical mechanics attempts to situate equilibrium at the macroscopic level in the Boltzmann approach and at the statistical level in the Gibbs approach. The aim of this talk is to propose a reconciliation between these approaches and to do so we need to reconsider the concept of equilibrium. Our proposal is that the binary property of the system being or not being in equilibrium is dropped in favour of a continuous property.

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Exploring the Milky Way's Ecosystem: Recycling of Gas on a Galactic Scale

Dr. Tyler Foster
Brandon University

Analysis on a Non-Archimedean Field and Applications in Physics

Dr. Khodr Shamseddine
Department of Mathematics
Western Illinois University

In this talk, my recent work on non-Archimedean fields will be summarized. In particular, I will present results about the convergence and analytical properties of power series over the Levi-Civita field and show that they have the same smoothness behavior as real power series. Then I will introduce a measure on the field that leads naturally to an integration theory with similar properties to those of the Lebesgue integral of Real Analysis. Moreover, I will discuss solutions to one-dimensional and multi-dimensional optimization problems with or without constraints.
Applications of my mathematical research in Physics will then be discussed. For example, using calculus on the Levi-Civita field and the existence of infinitely small numbers in the field, I will show how to accurately and efficiently compute the derivatives of real functions representable on a computer up to very high orders (whenever they exist). I will also give an overview of current and future research projects with potential impact in various areas of Theoretical Physics.

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Electron Scattering and Hadron Structure

Dr. Garth Huber
University of Regina

Electron scattering from light mesons and nucleons provides precise information about the ground state structure of matter. In this talk, I present a survey of recent experimental progress on the electromagnetic structure of pions, kaons and nucleons.

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From Structure to function: modern structural biology approaches

Dr. Jörg Stetefeld
Dept. of Chemistry, University of Manitoba

Modern structural biology laboratories follow an “integrated approach” performing a combination of different structural (X-ray Crystallography and multidimensional NMR, SAXS and EXAFS) and biophysical techniques (different spectroscopical applications, ultracentrifugation and trFRET) together with a deepview biochemical-functional study. The talk will describes three key systems in focus of our research interest with the goal (i) to shed light into the domain communication of a negative cooperative enzyme (GSAM) [1], (ii) to apply the storage and delivery function of coiled-coil domains (RHCC) [2, 3], and (iii) to investigate the key function of agrin in neuromuscular synapse formation [4-7].

1.Stetefeld, J., M. Jenny, and P. Burkhard, Intersubunit signaling in
glutamate-1-semialdehyde-aminomutase. Proc Natl Acad Sci U S A, 2006. 103(37):
p. 13688-93.

2.Stetefeld, J., et al., Crystal structure of a naturally occurring parallel
right-handed coiled coil tetramer. Nat Struct Biol, 2000. 7(9): p. 772-6.

3.Ozbek, S., et al., Favourable mediation of crystal contacts by
cocoamidopropylbetaine (CAPB). Acta Crystallogr D Biol Crystallogr, 2005. 61(Pt
4): p. 477-80.

4.Stetefeld, J., et al., The laminin-binding domain of agrin is structurally
related to N-TIMP-1. Nat Struct Biol, 2001. 8(8): p. 705-9.

5.Stetefeld, J., et al., Modulation of agrin function by alternative splicing
and Ca2+ binding. Structure (Camb), 2004. 12(3): p. 503-15.

6.Stetefeld, J. and M.A. Ruegg, Structural and functional diversity generated by
alternative mRNA splicing. Trends Biochem Sci, 2005. 30(9): p. 515-21.

7.Mascarenhas, J.B., et al., Mapping of the laminin-binding site of the
N-terminal agrin domain (NtA). Embo J, 2003. 22(3): p. 529-36.

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