Browsing 2013 by MFO Scientific Program "Research in Pairs 2012"

Now showing items 1-9 of 9

    • Calculating conjugacy classes in Sylow p-subgroups of finite Chevalley groups of rank six and seven 

      [OWP-2013-10] Goodwin, Simon M.; Mosch, Peter; Röhrle, Gerhard (Mathematisches Forschungsinstitut Oberwolfach, 2013-04-10)
      Let $G(q)$ be a finite Chevalley group, where $q$ is a power of a good prime $p$, and let $U(q)$ be a Sylow $p$-subgroup of $G(q)$. Then a generalized version of a conjecture of Higman asserts that the number $k(U(q))$ of ...

    • G-complete reducibility in non-connected groups 

      [OWP-2013-09] Bate, Michael; Herpel, Sebastian; Martin, Benjamin; Röhrle, Gerhard (Mathematisches Forschungsinstitut Oberwolfach, 2013-04-10)
      In this paper we present an algorithm for determining whether a subgroup $H$ of a non-connected reductive group $G$ is $G$-completely reducible. The algorithm consists of a series of reductions; at each step, we perform ...

    • Legendrian rational unknots in lens spaces 

      [OWP-2013-06] Geiges, Hansjörg; Onaran, Sinem (Mathematisches Forschungsinstitut Oberwolfach, 2013-03-14)
      We classify Legendrian rational unknots with tight complements in the lens spaces $L(p,1)$ up to coarse equivalence. As an example of the general case, this classification is also worked out for $L(5, 2)$. The knots are ...

    • Low rank differential equations for hamiltonian matrix nearness problems 

      [OWP-2013-01] Guglielmi, Nicola; Kreßner, Daniel; Lubich, Christian (Mathematisches Forschungsinstitut Oberwolfach, 2013-02-08)
      For a Hamiltonian matrix with purely imaginary eigenvalues, we aim to determine the nearest Hamiltonian matrix such that so me or all eigenvalues leave the imaginary axis. Conversely, for a Hamiltonian matrix with all ...

    • Multiple Bernoulli series and volumes of moduli spaces of flat bundles over surfaces 

      [OWP-2013-04] Baldoni, Maria Welleda; Boysal, Arzu; Vergne, Michèle (Mathematisches Forschungsinstitut Oberwolfach, 2013-03-14)
      Using Szenes formula for multiple Bernoulli series, we explain how to compute Witten series associated to classical Lie algebras. Particular instances of these series compute volumes of moduli spaces of flat bundles over ...

    • Near critical density irregular sampling in bernstein spaces 

      [OWP-2013-16] Olevskij, Aleksandr M.; Ulanovskii, Alexander (Mathematisches Forschungsinstitut Oberwolfach, 2013-07-23)
      We obtain sharp estimates for the sampling constants in Bernstein spaces when the density of the sampling set is near the critical value.

    • Noncompact harmonic manifolds 

      [OWP-2013-08] Knieper, Gerhard; Peyerimhoff, Norbert (Mathematisches Forschungsinstitut Oberwolfach, 2013-04-10)
      The Lichnerowicz conjecture asserts that all harmonic manifolds are either flat or locally symmetric spaces of rank 1. This conjecture has been proved by Z.I. Szab ́o [Sz] for harmonic manifolds with compact universal ...

    • On the Derived Category of Grassmannians in Arbitrary Characteristic 

      [OWP-2013-24] Buchweitz, Ragnar-Olaf; Leuschke, Graham J.; Van den Bergh, Michel (Mathematisches Forschungsinstitut Oberwolfach, 2013-12-09)
      In this paper we consider Grassmannians in arbitrary characteristic. Generalizing Kapranov's well-known characteristic-zero results we construct dual exceptional collections on them (which are however not strong) as well ...

    • On the geometry of regular maps from a quasi-projective surface to a curve 

      [OWP-2013-03] Parameswaran, A. J.; Tibăr, Mihai-Marius (Mathematisches Forschungsinstitut Oberwolfach, 2013-03-14)
      We explore consequences of the triviality of the monodromy group, using the condition of purity of the mixed Hodge structure on the cohomology of the surface X.