Associate Professor Simon Colin Harris

Ph.D. Mathematics, Part III Mathematics (distinction), B.A. Mathematics (First class), University of Cambridge, UK.

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Associate Professor


I joined the University of Auckland in April 2018 as an Associate Professor of Probability in the Department of Statistics. Prior to moving to New Zealand, I spent many years at the University of Bath, United Kingdom. In Bath, I was one of the founding members of ProbL@B which is internationally recognised as a world class probability centre. I contributed to the great success of the lab over many years and my leadership was a major factor in ProbL@B becoming a centre of excellence in branching processes.

In 2012-13, I was appointed as professeur invité at LPMA, a world class centre for probability at the prestigious Université Pierre et MarieCurie, Paris.

  • 2018-present  Associate Professor, University of Auckland, NZ.
  • 2017-2018   Reader in Probability, University of Bath, UK.
  • 2012-2013   Professeur invité, Université Pierre et Marie Curie, Paris, France.
  • 2009-2017   Senior Lecturer in Probability, University of Bath, UK.
  • 1994-2009   Lecturer in Statistics, University of Bath, UK.

Research | Current

My main research interests lie in probability theory, especially branching processes. My work also touches on other areas of mathematics, such as non-linear PDEs whose solutions have probabilistic representations.

I often aim to understand fundamental stochastic population models by making intuitive ideas and heuristic arguments about their behaviour into rigorous, and ideally elegant, mathematics. Typical questions involving branching processes might concern the growth rate of a population, how fast new territory is colonised, the probability a population survives, the effects of selection, or genealogies of certain individuals.

I am internationally recognised as a leading expert within my field, having published in some of the top international journals in mathematics spanning the areas of probability, analysis and mathematical physics. I am experienced leading research projects and enjoy working in international collaborations. My research has received funding from UK’s EPSRC, and I have been Lead scientist for an EU Marie-Curie Intra-European Fellowship.

Teaching | Current

Stats320 Applied Stochastic Modelling (Semester 1). Introduction to stochastic modelling, with an emphasis on examples. Applications involving Markov chains, Poisson processes, and queues will be investigated by using theory and simulation.

Stats325/Stats721 Stochastic Processes (Semester 2). Introduction to stochastic processes, including theory, methods and applications. Models will include Branching processes, Markov chains and random walks.

Stats710 Probability Theory (Semester 2).  Fundamental ideas of probability theory in a general & rigorous framework. Includes topics such as axioms of probability, information encoded by sigma-algebras, conditional expectations, laws of large numbers, Central Limit Theorem, martingales and generating functions.

Undergraduate project supervision. I am usually able to offer a wide variety of projects on probability. Just ask!

Postgraduate supervision

I have successfully supervised 9 PhD students and 2 postdoctoral positions, with several going on to successful academic careers.

I am always happy to discuss supervising research projects in probability theory, especially related to stochastic population models, branching processes, coalescents, Brownian motions, and mathematical population genetics. 

Competitive PhD funding may be available for excellent national or international applicants.

Areas of expertise

My main research lies in probability theory, including stochastic population models, branching processes, branching Brownian motions, coalescent processes, martingales, and fragmentations. Other interests include non-linear PDEs that have probabilistic representations, such as Fisher-KPP reaction-diffusion equations via Brownian motions.

Committees/Professional groups/Services

Research Committee member, Department of Statistics 

NZ Statistical Association member

NZ Mathematical Society member

Selected publications and creative works (Research Outputs)

  • Berestycki, J., Brunet É, Harris, S. C., & Miłoś P (2017). Branching Brownian motion with absorption and the all-time minimum of branching Brownian motion with drift. Journal of Functional Analysis, 273 (6), 2107-2143. 10.1016/j.jfa.2017.06.006
  • Berestycki, J., Brunet É, Harris, S. C., & Roberts, M. (2017). Vanishing corrections for the position in a linear model of FKPP fronts. Communications in Mathematical Physics, 349 (3), 857-893. 10.1007/s00220-016-2790-9
  • Harris, S. C., & Roberts, M. I. (2017). The many-to-few lemma and multiple spines. Annales de l'institut Henri Poincaré - Probabilités et Statistiques (Probability and Statistics), 53 (1), 226-242. 10.1214/15-AIHP714
  • Harris, S. C., Hesse, M., & Kyprianou, A. E. (2016). Branching Brownian motion in a strip: Survival near criticality. Annals of Probability, 44 (1), 235-275. 10.1214/14-AOP972
  • Bocharov, S., & Harris, S. C. (2016). Limiting distribution of the rightmost particle in catalytic branching Brownian motion. Electronic Communications in Probability, 2110.1214/16-ECP22
  • Berestycki, J., Brunet É, Harris, J. W., Harris, S. C., & Roberts, M. I. (2015). Growth rates of the population in a branching Brownian motion with an inhomogeneous breeding potential. Stochastic Processes and their Applications, 125 (5), 2096-2145. 10.1016/

Contact details

Primary office location

SCIENCE CENTRE 303 - Bldg 303
Level 3, Room 319
New Zealand