#### Michel Zoeteman, PhD student at the Division of Algebra and Geometry

Start date: August 26, 2019

My research interests lie in the field of number theory, especially the theory of diophantine equations. This is a topic that combines analytic, algebraic and geometric methods in order to decide whether or not a given diophantine equation has solutions in the integers. I will in particular focus on how Fourier-analytic methods can be used to establish asymptotic formulae for the number of solutions.

Previously I studied mathematics at the University of Leiden, where I worked on questions related to the ternary Goldbach problem, Artin's primitive root conjecture as well as mixed exponential and polynomial equations.

#### Nikolay Pochekai, PhD student at the Division of Analysis and Probability Theory

Start date: August 26, 2019

I studied operator algebras in Kyiv National University and algebraic geometry in Higher School of Economics (Moscow). Now I am interested in bivariant K-theory and microlocal analysis.

#### Julia Larsson, industrial PhD student in the graduate school Applied Mathematics and Mathematical Statistics

Start date: August 19, 2019

My research as an industrial PhD student at Fraunhofer-Chalmers Centre is about developing mathematical models that can aid in drug discovery. The models in question should be able to describe how the body affects the drug and how the drug affects the body, and at the same time capture the inter-individual variability that arises from the drug reacting differently between individuals. On top of that, the systems of particular interest in my research are those with time-varying or non-existing baseline. That means that the concentration of the drug target is not constant or even zero in healthy individuals, which makes it difficult to measure the actual effect of the drug. To tackle these problems, I use techniques from dynamical systems, pharmacokinetic/pharmacodynamic modelling and Non-Linear Mixed Effects modelling.

I started as a student at Chalmers in 2014 and have a Bachelor's degree in Biotechnology and a Master's degree in Engineering mathematics and computational science.

#### PhD student at the Division of Analysis and Probability Theory

Start date: August 15, 2019

My research interest is broad and spans over branches of geometry, analysis, applications in ecology, imaging and physics, and game theory. Using a game theoretical model, we show how diversity is a successful strategy for survival among microbes by finding Nash equilibria and developing new concepts to games. In geometry, I’m focusing on gradient flows. These are useful tools in image analysis and in theoretical physics.

#### Anna Holmlund, PhD student at the Division of Algebra and Geometry

Start date: August 15, 2019

I am a PhD student in mathematics education; I take part in CUL:s research school. I am an upper secondary teacher in mathematics and physics, and during the last few years I have worked at the NTI-gymnasiet in Gothenburg. My research interest in mathematics education is based on my wish to learn more about scientific questions relevant to my work. In my research I aim to focus on what aspects of relevant algebraic concepts that are critical for students, and in what way these aspects are varied in the teaching of the subject.

#### Malin Nilsson, PhD student at the Division of Applied Mathematics and Statistics

Start date: August 15, 2019

My research will be focused on numerical solution of partial differential equations. I will develop and analyze efficient algorithms for problems with heterogeneous data. Heterogeneous materials are common both in nature and the manufacturing industry. One example is composite materials that are designed to have optimal properties for a certain purpose. Heterogeneous materials are a great challenge both in the mathematical and the numerical analysis.

I have a bachelor and a master degrees in mathematics from the University of Gothenburg and spent my last year as an exchange student at the University of Kaiserslauten.

#### Antti Perälä, guest teacher at the Division of Analysis and Probability Theory

Start date: August 1, 2019

My research focuses on functional analysis, complex variables and operator theory. In particular, I have been interested in various concrete operators (Toeplitz, Hankel, Volterra etc.) on spaces of analytic functions. Common topics are their operator theoretic properties and their spectra, as well as the related optimization problems. I am also interested in applications to other areas of mathematics and science.

I got my PhD in 2011 from the University of Helsinki, and since 2017 I have been a docent of the University of Eastern Finland. I started my work in Gothenburg in August 2019.

#### Axel Flinth, guest teacher at the Division of Analysis and Probability Theory

Start date: August 1, 2019

My research is dealing with theoretical aspects of mathematical signal processing, with focus on the application of optimization for signal reconstruction from linear measurements. A lot of my research operates within the field of “compressed sensing”, where assumptions about the structure of the signals are used for enabling, or enhancing, methods for reconstructing them. With the help of regularized optimization problems, and/or tailor-made algorithms, it is possible to reconstruct (extrinsically) n-dimensional objects from far fewer than n measurements.

My special interest is infinite-dimensional versions of the mentioned optimization problems. Especially appealing to me is that the field combines tools from many areas within mathematics: convex geometry, optimization, mathematical statistics and functional analysis.

I started my career within mathematics here in Gothenburg by attending math specializations in both grammar (at Nya Lundenskolan) and high school (at Hvitfeldtska gymnasiet). I was awarded my PhD from the Technische Universität Berlin in 2018, and has since then been working as a post-doc at Université de Toulouse.

#### Jakob Palmkvist, guest teacher at the Division of Algebra and Geometry

Start date: July 1, 2019

My research concerns algebraic structures that arise in fundamental physics, in particular Lie algebras describing duality symmetries in string theory and extensions to infinite-dimensional Lie superalgberas. A new type of such extensions, called tensor hierarchy algebras, have proven particularly useful in models where we generalize diffeomorphisms and other geometric concepts used to describe ordinary gravity in general relativity. The generalized diffeomorphisms unify ordinary diffeomorphisms with gauge transformations related to the duality symmetries and can lead to a better understanding of how general theory should be unified with quantum mechanics.

I obtained my PhD at Chalmers 2008 after graduate studies at the Albert Einstein Institute in Potsdam, and have subsequently been a postdoc/researcher at the Université Libre de Bruxelles, Institut des Hautes Études Scientifiques, Chalmers, and Texas A&M University. During the first half of the autumn term 2019, I will teach discrete mathematics for the engineering programmes in computer science.

#### Moritz Schauer, associate senior lecturer at the Division of Applied Mathematics and Statistics

Start date: July 1, 2019

I am working on statistical theory and methodology for dynamical stochastic models such as stochastic differential equations. In general, dynamical stochastic models describe the evolution of processes and systems which have dynamics with temporal or spatial interactions and show stochastic behaviour.

Applications of such models are found in all areas, be it to model the change in the extension of the West Antarctic ice shelf, the interaction of neurons in the brain or the deformation of tissue during tumour growth.

In particular I am interested in statistical inference for nonlinear stochastic differential equations from indirect observation, using Bayesian approaches to inference. I work on finding inference procedures for such models with provably good statistical properties, using modern probability theory and stochastic calculus and the theory of non-parametric Bayesian inference and I work on their computational implementation using advanced Markov Chain Monte Carlo techniques.

After I completed my PhD at the Delft University of Technology in the Netherlands in 2015, I worked at the Korteweg-de Vries Institute for Mathematics, University of Amsterdam and at the Mathematical Institute of Leiden University.

#### Sonja Göc, study guidance counsellor for mathematics students at the University of Gothenburg

Start date: June 10, 2019

I work as a study guidance counsellor for the bachelor's programme in Mathematics, the master's programme in Mathematical Sciences, the teacher education programme and courses in mathematics and mathematical statistics at the University of Gothenburg. I inform among other things about the structure and content of the programmes and the courses, and about regulations that apply when studying at the University of Gothenburg. I have individual and group guidance discussions and make individual study plans.

Earlier, I was study guidance counsellor at Chalmers, with a special responsibility for Engineering Physics.

#### Thomas Bäckdahl, senior lecturer at the Division of Analysis and Probability Theory

Start date: March 25, 2019

My research focuses on mathematical problems coming from Einstein's theory of general relativity, in particular questions concerning black holes. From a mathematical point of view I study linear and non-linear hyperbolic evolution equations on strongly curved Lorentzian manifolds. In particular I am interested in proving non-linear stability of Kerr black holes, which is one of the most important open problems in this field. I am developing tools to handle this using computer algebra and a powerful spinor formalism revealing deep geometric structures as well as PDE techniques like local integrated decay estimates. Together with international colleagues I have now written a proof of the linearized problem for slowly rotating black holes, but the non-linear problem still requires much work.

I have just started teaching a course in linear algebra and numerical analysis for the F and TM programs.

After completing my PhD in mathematics in Linköping, I have spent many years as a postdoc at Institut Mittag-Leffler in Stockholm, Queen Mary University of London, the Albert Einstein Institute in Potsdam and the University of Edinburgh. I have also been a guest lecturer here in Gothenburg and most recently senior lecturer at Örebro University.