Recent Papers

2011

  • First cohomology groups of Chevalley groups in cross characteristic, Annals of Math. 174 (2011), 543 - 559 (joint work with R. M. Guralnick).

  • Waring problem for finite simple groups, Annals of Math. (to appear, joint work with M. Larsen and A. Shalev).

  • A reduction theorem for the Alperin Weight Conjecture, Invent. Math. 184 (2011), 529 - 565 (joint work with G. Navarro).

  • Representation growth in positive characteristic and conjugacy classes of maximal subgroups, Duke Math. J. (to appear, joint work with R. M. Guralnick and M. Larsen).

  • A problem of Kollar and Larsen on finite linear groups and crepant resolutions, J. Europ. Math. Soc. (to appear, joint work with R. M. Guralnick).

  • Brauer's height zero conjecture for the 2-blocks of maximal defect, J. Reine Angew. Math. (to appear, joint work with G. Navarro).

  • Commutators in finite quasisimple groups, Bull. London Math. Soc. (to appear, joint work with M. Liebeck, E. O'Brien, and A. Shalev).

  • Products of squares in finite simple groups, Proc. Amer. Math. Soc. (to appear, joint work with M. Liebeck, E. O'Brien, and A. Shalev).

  • Cycle indices for finite orthogonal groups of even characteristic, Trans. Amer. Math. Soc. (to appear, joint work with J. Fulman and J. Saxl).

  • Real class sizes and real character degrees, Math. Proc. Camb. Philos. Soc. 150 (2011), 47 - 71 (joint work with R. M. Guralnick and G. Navarro)

    2010

  • The Ore conjecture, J. Europ. Math. Soc. 12 (2010), 939 -1008 (joint work with M. Liebeck, E. O'Brien, and A. Shalev) (Early version).

  • Degrees of rational characters of finite groups, Adv. Math. 224 (2010), 1121 - 1142 (joint work with G. Navarro).

  • Representations of general linear groups which are irreducible over subgroups, Amer. J. Math. 132 (2010), 425 - 473 (joint work with A. S. Kleshchev).

  • Dual pairs of finite classical groups in cross characteristic, Contemp. Math. 524 (2010), pp. 161 - 179.

  • On p-Brauer characters of p'-degree and self-normalizing Sylow p-subgroups, J. Group Theory 13 (2010), 785 - 797 (joint work with G. Navarro).

  • Non-vanishing elements of finite groups, J. Algebra 323 (2010), 540 - 545 (joint work with S. Dolfi, G. Navarro, E. Pacifici, and L. Sanus).

  • Brauer characters of prime power degrees and conjugacy classes of prime power lengths, Alg. Colloq. 17 (2010), 541- 548 (joint work with W. Willems).

    2009

  • Groups with just one character degree divisible by a given prime, Trans. Amer. Math. Soc. 361 (2009), 6521 - 6547 (joint work with I. M. Isaacs, A. Moreto, and G. Navarro).

  • Representations of finite special linear groups in non-defining characteristic, Adv. Math. 220 (2009), 478 - 504 (joint work with A. S. Kleshchev) ( Early version, arXiv:0810.0849v1 [math.RT]).

  • Real characters and degrees, Israel J. Math. 171 (2009), 157 - 173 (joint work with G. Navarro and L. Sanus).

  • On the restriction of cross characteristic representations of ^{2}F_{4}(q) to proper subgroups, Archiv Math. 93 (2009), 415 - 423 (joint work with F. Himstedt and H. N. Nguyen).

    2008

  • Symmetric powers and a conjecture of Kollar and Larsen, Invent. Math. 174 (2008), 505 - 554 (joint work with R. M. Guralnick) (Early version, arXiv:0810.0853v1 [math.RT]).

  • Hall-Higman type theorems for semisimple elements of finite classical groups, Proc. London Math. Soc. 97 (2008), 623 - 668 (joint work with A. E. Zalesskii) (Early version, arXiv:0810.0855v1 [math.RT]).

  • Rational irreducible characters and rational conjugacy classes in finite groups, Trans. Amer. Math. Soc. 360 (2008), 2443 - 2465 (joint work with G. Navarro).

  • Primes dividing the degrees of the real characters of finite groups, Math. Z. 259 (2008), 755 - 774 (joint work with S. Dolfi and G. Navarro).

  • Brauer characters with cyclotomic field of values, J. Pure Appl. Alg. 212 (2008), 628 - 635 (joint work with G. Navarro and A. Turull).

  • Prime divisors of character degrees, J. Group Theory 11 (2008), 341 - 356 (joint work with A. Moreto).

  • Cross characteristic representations of ^{3}D_{4}(q) are reducible over proper subgroups, with an appendix by F. Himstedt, J. Group Theory 11 (2008), 657 - 668 (joint work with H. N. Nguyen).

    2007

  • Groups with two real Brauer characters, J. Algebra 307 (2007), 891 - 898 (joint work with G. Navarro and L. Sanus).

  • On the Navarro-Willems conjecture for blocks of finite groups, J. Pure Appl. Algebra 208 (2007), 481 - 484 (joint work with C. Bessenrodt, G. Navarro, and J. Olsson) (dvi file), (Addendum).

  • p-rational characters and self-normalizing Sylow p-subgroups, Represent. Theory 11 (2007), 84 - 94 (joint work with G. Navarro and A. Turull).

  • Mutually unbiased bases and orthogonal decompositions of Lie algebras, Quantum Information and Communication, 7 (2007), 371 - 382 (joint work with P. Boykin, M. Sitharam, and P. Wocjan).

    2006

  • Characters of p'-degree with cyclotomic field of values, Proc. Amer. Math. Soc. 134 (2006), 2833 - 2837 (joint work with G. Navarro).

  • Rational Brauer characters, Math. Annalen 335 (2006), 675 - 686 (joint work with G. Navarro).

  • Finite groups admitting grassmannian 4-designs, J. Algebra 306 (2006), 227 - 243.

    2005

  • Real conjugacy classes in algebraic groups and finite groups of Lie type, J. Group Theory 8 (2005), 291 - 315 (joint work with A. E. Zalesski).

  • Decompositions of small tensor powers and Larsen's conjecture, Represent. Theory 9 (2005), 138 - 208 (joint work with R. M. Guralnick) (dvi file).

  • Rank 3 permutation modules for finite classical groups, J. Algebra 291 (2005), 551 - 606 (joint work with P. Sin).

  • The non-coprime k(GV)-problem, J. Algebra 293 (2005), 185-242 (joint work with R. M. Guralnick).

    2004

  • Unipotent elements of finite groups of Lie type and realization fields of their complex representations, J. Algebra 271 (2004), 327 - 390 (joint work with A. E. Zalesskii).

  • On restrictions of modular spin representations of symmetric and alternating groups, Trans. Amer. Math. Soc. 356 (2004), 1971-1999 (joint work with A. S. Kleshchev).

  • Cross characteristic representations of even characteristic symplectic groups, Trans. Amer. Math. Soc. 356 (2004), 4969 - 5023 (joint work with R. M. Guralnick).

    2003

  • The modulo 2 structure of rank 3 permutation modules for odd characteristic symplectic groups, J. Algebra 268 (2003), 463 - 483 (joint work with J. M. Lataille and P. Sin).

  • Finite simple unisingular groups of Lie type, J. Group Theory 6 (2003), 271 - 310 (joint work with R. M. Guralnick).

  • Low dimensional representations of finite quasisimple groups, Proceedings of the London Math. Soc. Symposium ``Groups, Geometries, and Combinatorics'', Durham, July 2001, A. A. Ivanov et al eds., World Scientific, 2003, N. J. 277 - 294.

    2002

  • Irreducibility of tensor squares, symmetric squares, and alternating squares, Pacific J. Math. 202 (2002), 379 - 427 (joint work with K. Magaard and G. Malle).

  • Mod p reducibility of unramified representations of finite groups of Lie type, Proc. London Math. Soc. 84 (2002), 439 - 472 (joint work with A. E. Zalesskii).

  • Reducibility modulo p of complex representations of finite groups of Lie type: Asymptotical result and small characteristic case, Proc. Amer. Math. Soc. 130 (2002), 3177 - 3184 (joint work with A. E. Zalesskii).

  • Cross characteristic representations of symplectic groups and unitary groups, J. Algebra 257 (2002), 291 - 347; Addendum, J. Algebra 299 (2006), 443 - 446, (joint work with R. M. Guralnick, K. Magaard, and J. Saxl).

    2001

  • Irreducible tensor products of representations of quasi-simple finite groups of Lie type, in: Modular Representation Theory of Finite Groups (M. Collins, B. Parshall, L. Scott, eds.) Walter de Gruyter, Berlin 2001, 239 - 262 (joint work with K. Magaard).

  • Symmetric squares, spherical designs, and lattice minima, J. Algebra 240 (2001), 185 - 208 (joint work with W. Lempken and B. Schroeder).

    2000

  • Some aspects of finite linear groups: A survey, J. Math. Sciences 100 (2000), 1893 - 1914 (joint work with A. E. Zalesskii). (dvi file)

    1999

  • Low-dimensional representations of special linear groups in cross characteristic, Proc. London Math. Soc. 78 (1999), 116 - 138 (joint work with R. Guralnick).

  • Symplectic group lattices, Trans. Amer. Math. Soc. 351 (1999), 2101 -- 2139 (joint work with R. Scharlau).

  • Lower bounds for the minima of certain symplectic and unitary group lattices, Amer. J. Math. 121 (1999), 889 - 918 (joint work with N. Dummigan).

  • Globally irreducible representations of SL(3,q) and SU(3,q), Israel J. Math. 109 (1999), 225 - 251.

  • Modular representations of GL(3,p), symmetric squares, and mod-p cohomology of GL(3,Z), J. Algebra 222 (1999), 376 - 399 (joint work with A. Ash).

  • Globally irreducible lattices, Contemp. Math. 249 (1999), 97 - 111.

    1998

  • Congruences for certain theta series, J. Number Theory 77 (1998), 86 - 105 (joint work with N. Dummigan).

  • The p-intersection subgroups in quasi-simple and almost simple finite groups, J. Algebra 207 (1998), 1 - 42 (joint work with P. Fleischmann and W. Lempken).

  • The primitive p-Frobenius groups, Proc. Amer. Math. Soc. 126 (1998), 1337 - 1343 (joint work with P. Fleischmann and W. Lempken).