J  A  S  O  N     B  E  H  R  S  T  O C  K

My primary research areas are in geometric group theory and low-dimensional topology.
Specialties: Mapping class groups, relatively hyperbolic groups, hierarchical hyperbolicity, 3-manifold groups, Teichmuller theory, Artin groups, asymptotic geometry, quasi-isometric rigidity. I also am interested in probabilistic combinatorics.

My papers are available for download via the ArXiv and are also available below as PDF files.
Bibliographic and citation information can also be found at: Google Scholar, MathSciNet, and zbMATH.

• A threshold for relative hyperbolicity in random right-angled Coxeter groups, with A. Ciceksiz and V. Falgas-Ravry
  
• Relative hyperbolicity, thickness, and the hierarchically hyperbolic boundary, with C. Abbott and J. Russell
        To appear in Michigan Mathematical Journal.
• Structure invariant properties of the hierarchically hyperbolic boundary, with C. Abbott and J. Russell
        To appear in Journal of Topology & Analysis.
• Square percolation and the threshold for quadratic divergence in random right-angled Coxeter groups, with V. Falgas-Ravry and T. Susse
        Random Structures and Algorithms, vol. 60, 594-640, 2022.
• A combinatorial take on hierarchical hyperbolicity and applications to quotients of mapping class groups, with M. Hagen, A. Martin, and A. Sisto
        To appear in Journal of Topology.
• Conjugator lengths in hierarchically hyperbolic groups, with C. Abbott
        Geometry, Groups, and Dynamics, vol. 17, 805-838, 2023.
• Quasiflats in hierarchically hyperbolic spaces, with M. Hagen and A. Sisto
        Duke Mathematical Journal, vol. 170, 909-996, 2021.
• Largest acylindrical actions and stability in hierarchically hyperbolic groups, with C. Abbott and M. Durham, and an appendix written by D. Berlyne and J. Russell
        Transactions of the American Mathematical Society, vol. 8, 66--104, 2021.
• A counterexample to questions about boundaries, stability, and commensurability.
        Beyond Hyperbolicity, London Mathematical Society Lecture Note Series no. 454.
• Asymptotic dimension and small-cancellation for hierarchically hyperbolic spaces and groups, with M. Hagen and A. Sisto
        Proceedings of the London Mathematical Society, vol. 114, 890-926, 2017.
• Hierarchically hyperbolic spaces II: combinations theorems and the distance formula, with M. Hagen and A. Sisto
        Pacific Journal of Mathematics, vol. 299, 257-338, 2019.
• Global structural properties of random graphs, with V. Falgas-Ravry, M. Hagen and T. Susse
        International Mathematics Research Notices, vol. 2018, 1411-1441, 2018.
        Supplementary source code for experimenting with structural properties in random graphs and also the full data referenced in the paper.
• Combinatorial higher dimensional isoperimetry and divergence, with C. Drutu
        Journal of Topology & Analysis, vol 11, 499-534, 2019.
• Hierarchically hyperbolic spaces I: curve complexes for cubical groups, with M. Hagen and A. Sisto
        Geometry & Topology, vol. 21, 1731-1804, 2017.
• Thickness, relative hyperbolicity, and randomness in Coxeter groups, with M. Hagen and A. Sisto, with an appendix written jointly with P.-E. Caprace
        Algebraic & Geometric Topology, vol. 17, 705-740, 2017.
        Supplementary source code for experimenting with random Coxeter groups.
• Higher dimensional divergence for mapping class groups, with C. Drutu
        Groups, Geometry, and Dynamics, vol. 13, 1035-1056, 2019.
• Cubulated groups: thickness, relative hyperbolicity, and simplicial boundaries, with M. Hagen
        Groups, Geometry, and Dynamics, vol. 10, 649--707, 2016.
• Divergence, thick groups, and short conjugators, with C. Drutu
        Illinois Journal of Mathematics, vol. 58, 939-980, 2014.
  
• Homomorphisms into mapping class groups. An addendum, with C. Drutu and M. Sapir
        Proceedings of the London Mathematical Society, vol. 3, 555-562, 2011.
        Online published version.
• Divergence and quasimorphisms of right-angled Artin groups, with R. Charney
        Mathematische Annalen, vol. 352, 339-356, 2012.
       Online published version.
• Quasi-isometric classification of non-geometric 3-manifold groups, with W. Neumann
        Journal Reine Angew. Math. (Crelle's Journal), vol. 669, 101-120, 2012.
• Quasi-isometric classification of some high dimensional right-angled Artin groups, with T. Januszkiewicz and W. Neumann
        Groups, Geometry, and Dynamics, vol. 4, 681-692, 2010.
• Median structures on asymptotic cones and homomorphisms into mapping class groups, with C. Drutu and M. Sapir
        Proceedings of the London Mathematical Society, vol. 3, 503--554, 2011.
        Online published version.
• Centroids and the rapid decay property in mapping class groups, with Y. Minsky
        Journal of the London Mathematical Society, vol. 84, 765-784, 2011.
• Growth of intersection numbers for free group automorphisms, with M. Bestvina and M. Clay
        Journal of Topology, vol. 3, 280-310, 2010.
• Geometry and rigidity of mapping class groups, with B. Kleiner, Y. Minsky, and L. Mosher
        Geometry & Topology, vol. 16, 781-888, 2012.
• Commensurability and QI classification of free products of finitely generated abelian groups, with T. Januszkiewicz and W. Neumann
        Proceedings of the American Mathematical Society, vol. 137, 811-813, 2009.
• Dimension and rank for mapping class groups, with Yair Minsky
        Annals of Mathematics, vol. 167, 1055-1077, 2008.
        Online published version.
• Quasi-isometric classification of graph manifolds groups, with W. Neumann
        Duke Mathematical Journal, vol. 141, 217-240, 2008.
        Duke University Press online published version, subscription required.
• Thick metric spaces, relative hyperbolicity, and quasi-isometric rigidity, with C. Drutu and L. Mosher
        Mathematische Annalen, vol. 344, 543--595, 2009.
• Asymptotic Geometry of the Mapping Class Group and Teichmuller Space
        (The last two sections of this paper contains results not in the Ph.D. thesis.)
        Geometry & Topology vol. 10, 1523-1578, 2006.
• Curve complexes and finite index subgroups of mapping class groups, with D. Margalit
        Geometriae Dedicata vol. 118, 71-85, 2006.
        Springer online published version, subscription required.
• Ph.D. Thesis: Asymptotic Geometry of the Mapping Class Group and Teichmuller Space
        SUNY Stony Brook Ph.D. Thesis, May 2004.

	Me with Harold and Tim at Banff International Research Station, Canada.	Me with Tim, Ivan, Jacob, and Daniel after a seminar.

• CUNY Geometry and Topology Seminar
  
• Columbia Geometric Topology Seminar
  
• Magnus Seminar (Group Theory Seminar at CUNY Graduate Center)