A PhD at Sofia

Written by Galina Lyutskanova-Zhekova, PhD student at IMI-BAS

In 2014, I graduated with a bachelor’s degree in applied mathematics and started studying in the master program “Computational Mathematics and Mathematical Modelling” at the Faculty of Mathematics and Informatics, Sofia University “St. Kliment Ohridski”. The master program provides many opportunities. The best one for my career growth was the Preparatory Modelling Week before the European Study Group with Industry 113, September 7 – 11, 2015, Sofia, Bulgaria, organized by the Faculty of Mathematics and Informatics (http://pmw2015.fmi.uni-sofia.bg/).

I participated in this event working on the project “Axisymmetric drop shape analysis’’, which was so interesting to me that I spent two months after the end of the Preparatory Modelling Week just researching different aspects of the project. Based on that research, I approached the instructor of the project, Dr. Tihomir Ivanov, with the request to become my master thesis advisor. He contacted Prof. Krassimir Danov with whom he had been working on a similar problem. Prof. Danov suggested several themes as potential topics of my master thesis. One of them, related with the modelling of the red blood cells, piqued my interest. I started working on this topic and graduated with a master’s degree in 2016. A year later I decided to start studying for a PhD in the Institute of Mathematics and Informatics at the Bulgarian Academy of Sciences. My idea was to continue working on similar problems and I asked Prof. Danov to become my PhD advisor. The topic of my thesis is “Modelling of nonlinear boundary problems of second and forth order with applications in chemistry and biology”. So far, I have worked on three different problems in my PhD studies:

1. The first one is to find the velocity and the dragging coefficient of a small spherical particle that is attached to the interface between two viscous fluids. The solution of this problem is important in the production of 2D-ordered micro- and nano-layers, which are applied in the production of solar panels, CCDs, and bio-memory chips.
2. The second problem is to calculate the electro-dipping force, acting on a dielectric particle, attached to the boundary between water and nonpolar fluid. This problem is important for the characterization of the surface charge density of micron-size objects and their three-phase contact angles.
3. The last one is the classical Bretherton problem. It describes the motion of an axisymmetric long bubble in circular capillary for small capillary numbers.

These problems are of a great interest to me and I would not have even heard of them if it were not for the master program “Computational Mathematics and Mathematical Modelling”. Because of that I would like to thank Prof. Stefka Dimova and Dr. Tihomir Ivanov for their efforts to organize in the frames of the master program events supporting the students in choosing their further professional paths.

And for everyone who is wondering whether to study for a PhD ─ based on my experience, it might be hard but it is worth it.

Let the mathematics be with you!