Professor Julien Berestycki

Associate Professor of Probability

Biographical Sketch

I was educated in France where I graduated jointly from ENSAE (National School for Statistics and Economic Administration) and Université Paris VI in 2000. After my PhD in Paris VI (2003) in Probability, I was Maitre de Conférences in Marseille for three years and then in Paris until 2014 when I joined the Department of Statistics and Magdalen College in Oxford.

During this time I have also twice been visiting professor at NYU-Abu Dhabi as well as a long term visitor at the University of Bath.

Research Interests

  • Branching processes
  • Branching random walks
  • Coalescence
  • Fragmentation
  • Population genetics
  • Reaction-diffusion equations
  • Front propigation
  • Random trees

My research is in probability theory and focuses essentially on models and situations which involve tree-like structures and branching phenomena. Examples include coalescent processes, branching processes, continuous random trees, branching random walks… These models are not only endowed with a remarkably rich mathematical structure that connects them to many area of mathematics, but they also occur naturally in physical sciences, in population genetics and in biology. Questions that arise in these fields are a major motivation of my work.

Publications

Berestycki, J. and Tough, O. (2024) “Selection principle for the $N$-BBM”, arXiv.
Berestycki, J., Liu, J., Mallein, B. and Schweinsberg, J. (2024) “Phase transition of the consistent maximal displacement of branching Brownian motion”, arXiv.
Berestycki, J., Kim, Y., Zeitouni, O., Mallein, B. and Lubetzky, E. (2024) “The extremal point process of branching brownian motion in Rd”, Annals of Probability, 52(3), pp. 955–982.
Berestycki, J., Graham, C., Kim, Y. and Mallein, B. (2023) “KPP traveling waves in the half-space”, arXiv.
Berestycki, J., Brunet, E., Nolen, J. and Penington, S. (2022) “Brownian bees in the infinite swarm limit”, Annals of Probability, 50(6), pp. 2133–2177.
Berestycki, J., Brunet, E., Cortines, A. and Mallein, B. (2022) “A simple backward construction of branching Brownian motion with large displacement and applications”, Annales de l’Institut Henri Poincaré, Probabilités et Statistiques, 58(4), pp. 2094–2113.
Berestycki, J., Brunet, E., Graham, C., Mytnik, L., Roquejoffre, J.-M. and Ryzhik, L. (2022) “The distance between the two BBM leaders”, Nonlinearity, 35(4), pp. 1558–1609.
Stasinski, R., Berestycki, J. and Mallein, B. (2021) “Derivative martingale of the branching Brownian motion in dimension d ≥ 1”, Annales de l’Institut Henri Poincaré, Probabilités et Statistiques, 57(3), pp. 1786–1810.
Berestycki, J., Brunet, E., Nolen, J. and Penington, S. (2021) “A free boundary problem arising from branching Brownian motion with selection”, Transactions of the American Mathematical Society, 374(9), pp. 6269–6329.
Berestycki, J., Brunet, É, Graham, C., Mytnik, L., Roquejoffre, J.-M. and Ryzhik, L. (2020) “The distance between the two BBM leaders.”

Contact Details

College Affiliation: Tutorial Fellow at Magdalen College

Email: julien.berestycki@stats.ox.ac.uk

Telephone: +44(0)1865 281881

Office number: 3.09

Graduate Students

David Geldbach

Research Groups

Probability