• A construction of hyperbolic Coxeter groups 

      [OWP-2010-04] Osajda, Damian (Mathematisches Forschungsinstitut Oberwolfach, 2010)
      We give a simple construction of Gromov hyperbolic Coxeter groups of arbitrarily large virtual cohomological dimension. Our construction provides new examples of such groups. Using this one can construct e.g. new groups ...
    • On Generalizations of Kac-Moody Groups 

      [OWP-2010-06] Blok, Rieuwert J.; Hoffman, Corneliu (Mathematisches Forschungsinstitut Oberwolfach, 2010-03-10)
      In [7] we define a Curtis-Tits group as a certain generalization of a Kac-Moody group. We distinguish between orientable and non-orientable Curtis-Tits groups and identify all orientable Curtis-Tits groups as Kac-Moody ...
    • On the Complement of the Richardson Orbit 

      [OWP-2010-09] Baur, Karin; Hille, Lutz (Mathematisches Forschungsinstitut Oberwolfach, 2010-03-13)
      We consider parabolic subgroups of a general algebraic group over an algebraically closed field $k$ whose Levi part has exactly $t$ factors. By a classical theorem of Richardson, the nilradical of a parabolic subgroup $P$ ...
    • Plethysms, replicated Schur functions and series, with applications to vertex operators 

      [OWP-2010-12] Fauser, Bertfried; Jarvis, Peter D.; King, Ronald C. (Mathematisches Forschungsinstitut Oberwolfach, 2010-03-14)
      Specializations of Schur functions are exploited to define and evaluate the Schur functions $s_\lambda [\alpha X]$ and plethysms $s_\lambda [\alpha s_\nu(X))]$ for any $\alpha$-integer, real or complex. Plethysms are then ...
    • Supertropical linear algebra 

      [OWP-2010-14] Izhakian, Zur; Knebusch, Manfred; Rowen, Louis (Mathematisches Forschungsinstitut Oberwolfach, 2010)
      The objective of this paper is to lay out the algebraic theory of supertropical vector spaces and linear algebra, utilizing the key antisymmetric relation of "ghost surpasses." Special attention is paid to the various ...