Ghislain St. Ives

I've been a PhD Student at UofC since the beginning of summer 2008.

Current project

I am currently working on simulation and analysis of defect mediated turbulence in 2D and 3D media. Turbulence in spatially extended pattern forming systems is often characterized by the appearance of topological defects (point defects in 2D and filaments in 3D [see image below]) that organize the local dynamics. In such defect mediated turbulence, it is common to characterize the dynamics by the rate at which these defects are dynamically created or annihilated in a given system. Although simple in principle, obtaining the rates experimentally or numerically can often prove quite challenging. Even without considering the effect of noise, these rates are often dominated by very short lived defects which can be misrepresented due to the sampling and act as an effective noise.

I have developed a robust method to detect, identify and track filaments in 3D based on filament collision events. With this, we plan to investigate qualitative differences in turbulent state generated by different underlying instabilities. In particular, we are interested in the so-called negative line tension instability and the twist instability, both being purely 3D phenomena that have very similar statistics. In the context of cardiac dynamics, it has been postulated that these two instabilities could play an important role in the transition from scroll wave to ventricular fibrillation. However, little is known about the effect that these instabilities have on the persistent turbulent dynamics.

Education

Undergraduate degree at Université du Québec à Trois-Rivières (one year doing a licence in biochemistry at Université de Montpellier II, France, at the occasion of an exchange program)

Master's degree in the interpretation of quantum mechanics under Prof. Louis Marchildon at Université du Québec à Trois-Rivières.

Publications & presentations

Ghislain St-Yves* and Joern Davidsen, Robustness of estimates of activity rates in defect-mediated turbulence, Jan 2012. [Poster presentation at Dynamics Days 2012 conference in Baltimore]

Ghislain St-Yves* and Joern Davidsen, Defect mediated turbulence in a locally quasiperiodic chemical medium, JCP, 133 (4), 044909, 2010.

Ghislain St-Yves* and Joern Davidsen, Defect mediated turbulence and the quasiperiodic route to chaos, June 2009. [Poster presentation at the Emergence in chemical systems II conference in Anchorage]

Ghislain St-Yves* and Joern Davidsen, Defect mediated turbulence and the quasiperiodic route to chaos, 2009. [Poster presentation at the annual MITACS conference at UNB, Fredericton]

Ghislain St-Yves*, Sur la réalité des mondes dans l'interprétation d'Everett de la mécanique quantique, 2007. [Master's thesis]

Ghislain St-Yves* and Louis Marchildon, The observer in Everett-inspired interpretation of Quantum Mechanics, 2007. [Poster presentation at the CAP (Canadian Association of Physicists) 2007 annual meeting at the University of Saskatchewan]

Contact information

Office

Science B, Room 504

Address

University of Calgary,
Department of Physics and Astronomy,
2500 University Drive NW,
Calgary, AB
T2N 1N4

E-mail
gstyves(at)ucalgary.ca