Yair Hartman

I'm a faculty member at the Math Department of Ben-Gurion University.

Before that, I was a postdoc at Northwestern University, a Ph.D. student of Omri Sarig at the Weizmann Institute and an M.Sc. student of Hillel Furstenberg at the Hebrew University.

Contact information:
Office: 207, Building 58.
E-mail: hartmany at bgu, then ac and il

Research interests:
Random walks on groups and Poisson boundary, Geometric Group Theory, Ergodic Theory and Operator Algebras.


  • Tight inclusions of C*-dynamical systems [arxiv]
    with Mehrdad Kalantar
  • Random Walks on Dense Subgroups of Locally Compact Groups [arxiv]
    with Michael Björklund and Hanna Oppelmayer
  • Kudo-Continuity Of Entropy Functionals [arxiv]
    with Michael Björklund and Hanna Oppelmayer
  • The Stabilized Automorphism Group of a Subshift [journal | arxiv]
    with Bryna Kra and Scott Schmieding
    International Mathematics Research Notices, 2021, rnab204.
  • Stationary C*-dynamical systems [arxiv]
    with Mehrdad Kalantar
    with an appendix with Uri Bader and Mehrdad Kalantar
    To appear in J. Eur. Math. Soc. (JEMS)
  • Choquet-Deny groups and the infinite conjugacy class property [journal | arxiv]
    with Joshua Frisch, Omer Tamuz and Pooya Vahidi Ferdowsi
    Annals of Mathematics Vol. 190, No. 1 (July 2019), pp. 307-320
  • Thompson's group F is not strongly amenable [journal | arxiv]
    with Kate Juscheno, Omer Tamuz and Pooya Vahidi Ferdowsi
    Ergodic Theory and Dynamical System Journal, 39 (2019) , pp. 925-929
  • Furstenberg Entropy of Intersectional Invariant Random Subgroups [journal | arxiv]
    with Ariel Yadin
    Compositio Mathematica 154 (10), 2239-2265
  • Generic stationary measures and actions [journal | 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

From the web



2020: (Linear) Algebra 2

2019 @ BGU: Linear Algebra for MME.

2018 @ Northwestern: Furstenberg-Poisson boundaries and Stationary Dynamical Systems. Here is a preliminary version of my lecture notes. Use with caution: there might be mistakes there and you're welcome to let me know about them!

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