Yair Hartman

I'm a Boas Assistant Professor (postdoc) at the department of mathematics, Northwestern University.
I completed my PhD at the Weizmann Institute under the supervision of Omri Sarig. My M.Sc. is from the Hebrew University and my adviser was Hillel Furstenberg.

Contact information:
Office: Lunt 312. E-mail: hartman at math.northwestern.edu

Research interests:
Random walks on groups and Poisson boundary, Geometric Group Theory, Ergodic Theory, Invariant Random Subgroups, Symbolic Dynamics, Cellular Autoamta.


  • Choquet-Deny groups and the infinite conjugacy class property [arxiv]
    with Joshua Frisch, Omer Tamuz and Pooya Vahidi Ferdowsi
  • Stationary C*-dynamical systems [arxiv]
    with Mehrdad Kalantar
    with an appendix with Uri Bader and Mehrdad Kalantar
  • Furstenberg Entropy of Intersectional Invariant Random Subgroups [arxiv]
    with Ariel Yadin
  • Thompson's group F is not strongly amenable [arxiv]
    with Kate Juscheno, Omer Tamuz and Pooya Vahidi Ferdowsi
    to appear in Ergodic Theory and Dynamical System Journal
  • Generic stationary measures and actions [arxiv]
    with Lewis Bowen and Omer Tamuz
    Trans. Amer. Math. Soc. 369 (2017) 4889-4929
  • Stabilizer rigidity in irreducible group actions [journal | arxiv]
    with Omer Tamuz
    Israel Journal of Mathematics, October 2016, Volume 216, Issue 2, pp 679-705
  • Property (T) and the Furstenberg Entropy of Nonsingular Actions [journal | arxiv]
    with Lewis Bowen and Omer Tamuz
    Proceedings of the American Mathematical Society, 144, no. 1 (2016): 31-39
  • Furstenberg entropy realizations for virtually free groups and lamplighter groups [journal|arxiv]
    with Omer Tamuz
    Journal d'Analyse Mathématique, April 2015, Volume 126, Issue 1, pp 227-257
  • An Abramov formula for stationary spaces [journal | arxiv]
    with Yuri Lima and Omer Tamuz
    Ergodic Theory and Dynamical Systems, 34 (2014), pp 837-853
  • Large semigroups of cellular automata [journal | arxiv]
    Ergodic Theory and Dynamical Systems, 32 (2012), pp 1991-2010



Winter 2018: Furstenberg-Poisson boundaries and Stationary Dynamical Systems. Here is a preliminary version of my lecture notes.

Fall 2017: Differential Calculus of Multivariable Functions (Math 230).

I worked as a TA at the Department of Mathematics, Ben-Gurion University, teaching the courses Algebra 1, Algebra 2 and Discrete math.