Papers

 
Publications and preprints are in pdf format (and some are in postscript or dvi formats). The dvi-files do not contain pictures.

  1. Homological and homotopical Dehn functions are different, pdf,
    with Aaron Abrams, Pallavi Dani and Robert Young.
    Proceedings of the National Academy of Sciences USA 110 (2013), no. 48, 19206--19212.
  2. Hyperbolic Hydra, pdf,
    with Will Dison and Tim Riley.
    Groups Geometry and Dynammics 7 (2013), no. 4, 961--976.
  3. Pushing fillings in right-angled Artin groups, pdf,
    with Aaron Abrams, Pallavi Dani, Moon Duchin and Robert Young.
    Journal of the London Mathematical Society (2013) 87, no. 3.
  4. Filling loops at infinity in the mapping class group, pdf,
    with Aaron Abrams, Pallavi Dani, Moon Duchin and Robert Young.
    Michigan Math. Journal 61 (2012), no. 4, 867--874.
  5. Super-exponential 2-dimensional Dehn functions, pdf ,
    with Josh Barnard and Pallavi Dani.
    Groups, Geometry and Dynamics 6 (2012), no. 1, 1--51.
  6. Turn graphs and extremal surfaces in free groups, pdf,
    with Matt Clay and Max Forester.
    Topology and geometry in dimension three, 171--178, Contemp. Math., 560 Amer. Math. Soc., Providence, RI, 2011.
  7. Morse theory and conjugacy classes of finite subgroups - II, pdf,
    with Matt Clay and Pallavi Dani.
    Geometriae Dedicata 147 (2010), 1--14.
  8. Density of isoperimetric spectra, pdf ,
    with Max Forester.
    Geometry & Topology 14 (2010) 435-472.
  9. The equation and groups that act freely on -trees, pdf,
    with Laura Ciobanu, Armando Martino and Shane O Rourke.
    Trans. Amer. Math. Soc. 361 (2009), no. 1, 223-236.
  10. Snowflake groups, Perron-Frobenius eigenvalues, and isoperimetric spectra, pdf version.
    with Martin R Bridson, Max Forester, and Krishnan Shankar.
    Geometry & Topology 13 (2009) 141-187.
  11. Morse theory and conjugacy classes of finite subgroups, pdf,
    with Matt Clay and Pallavi Dani.
    Geometriae Dedicata 135 (2008), 15--22.
  12. Super-exponential distortion of subgroups of CAT(-1) groups, pdf,
    with Josh Barnard and Pallavi Dani.
    Algebraic & Geometric Topology, 7 (2007), 301-308.
  13. The Geometry of the Word Problem for Finitely Generated Groups
    Advanced Courses in Mathematics - CRM Barcelona, Birkhauser Verlag, Basel, 2007. vii+206pp.
    Noel Brady, Tim Riley, Hamish Short.
  14. CAT(0) and CAT(-1) dimensions of torsion free hyperbolic groups, pdf.
    with J. Crisp
    Comment. Math. Helv. 82 (2007), no. 1, 61--85.
  15. Distortion of surface groups in CAT(0) free-by-cyclic groups, ps or pdf.
    with J. Barnard
    Geometriae Dedicata 120 (2006), 119--139.
  16. The length spectrum of a compact constant curvature complex is discrete, ps or pdf.
    with J. McCammond.
    Geom. Dedicata 119 (2006), 159--167.
  17. Bounding edge degrees in triangulated 3-manifolds, ps or pdf.
    with J. McCammond and J. Meier.
    Proceedings of the AMS 132 (2004), no. 1, 291--298.
  18. Local-to-asymptotic topology for cocompact CAT(0) complexes, ps.
    with J. McCammond and J. Meier.
    Topology and its Applications 131 (2003), no. 2, 177--188.
  19. Rigidity of Coxeter groups and Artin groups, ps.
    with J. McCammond, B. Muehlherr, and W. Neumann.
    Geometriae Dedicata, 94 (2002), no. 1, 91--109.
  20. On dimensions of CAT(0) and CAT(-1) complexes with the same hyperbolic group action, ps.
    with John Crisp.
  21. Two dimensional Artin groups with CAT(0) dimension three, ps or dvi.
    with John Crisp.
    Geometriae Dedicata 94 (2002) 185--214.
  22. The pure symmetric automorphisms of a free group form a duality group, ps.
    with J. McCammond, J. Meier, and A. Miller.
    Journal of Algebra, 246 (2001), no 2, 881--896.
  23. CAT(-1) structures for free-by-free groups, ps or dvi.
    (with A. Miller).
    Geometriae Dedicata. 90 (2002) 77--98.
  24. On algebraic and geometric dimensions for groups with torsion, ps or dvi.
    (with Ian J. Leary and Brita E. A. Nucinkis).
    Jour. London Math. Soc. (2) 64 (2001), no. 2, 489--500.
  25. Sol geometry groups are not asynchronously automatic, ps or dvi.
    Proc. London Math. Soc. (3) 83 (2001), no. 1, 93--119.
  26. There is only one gap in the isoperimetric spectrum, ps or dvi.
    (with M. R. Bridson).
    Geom. Funct. Anal. 10 (2000), no. 5, 1053--1070.
  27. Connectivity at infinity for right-angled Artin groups, ps or dvi.
    (with J. Meier).
    Trans. Amer. Math. Soc. 353 (2001), no. 1, 117--132.
  28. A note on finite subgroups of hyperbolic groups, ps or dvi.
    International Journal of Algebra and Computation, Vol. 10, No. 4 (2000), 399-405.
  29. Branched coverings of cubical complexes and subgroups of hyperbolic groups, ps or dvi.
    Jour. London Math. Soc., Vol 60 (1999), No. 2, 461--480.
  30. Filling-invariants at infinity for manifolds of nonpositive curvature, ps or dvi.
    (with B. Farb). Trans AMS, Vol.350, No.8 (1998), pp.3393-3405.
  31. Morse theory and finiteness properties of groups, ps or dvi.
    (with M. Bestvina). Invent. Math. Vol.129 (1997) pp.445-470.
  32. Asynchronous automatic structures on closed hyperbolic surface groups
    Geometric Group Theory (R. Charney, M. Davis, M. Shapiro eds.).
    OSU Math. Res. Inst. Publ. , Vol.3, de Gruyter, (1995)