• The Varchenko Determinant of a Coxeter Arrangement 

      [OWP-2017-33] Pfeiffer, Götz; Randriamaro, Hery (Mathematisches Forschungsinstitut Oberwolfach, 2017-11-24)
      The Varchenko determinant is the determinant of a matrix defined from an arrangement of hyperplanes. Varchenko proved that this determinant has a beautiful factorization. It is, however, not possible to use this factorization ...
    • Varieties of Invariant Subspaces Given by Littlewood-Richardson Tableaux 

      [OWP-2014-01] Kosakowska, Justyna; Schmidmeier, Markus (Mathematisches Forschungsinstitut Oberwolfach, 2014-04-25)
      Given partitions α,β,γ, the short exact sequences 0NαNβNγ0 of nilpotent linear operators of Jordan types α,β,γ, ...
    • Vector bundles on degenerations of elliptic curves and Yang-Baxter equations 

      [OWP-2007-04] Burban, Igor; Kreußler, Bernd (Mathematisches Forschungsinstitut Oberwolfach, 2007-03-22)
      In this paper we introduce the notion of a gemetric associative r-matrix attached to a genus one fibration with a section and irreducible fibres. It allows us to study degenerations of solutions of the classical Yang-Baxter ...
    • Very general monomial valuations of P2 and a Nagata type conjecture 

      [OWP-2013-22] Dumnicki, Marcin; Harbourne, Brian; Küronya, Alex; Roé, Joaquim; Szemberg, Tomasz (Mathematisches Forschungsinstitut Oberwolfach, 2013-10-29)
    • Virtual Polytopes 

      [OWP-2015-02] Panina, Gaiane; Streinu, Ileana (Mathematisches Forschungsinstitut Oberwolfach, 2015-04-10)
      Originating in diverse branches of mathematics, from polytope algebra and toric varieties to the theory of stressed graphs, virtual polytopes represent a natural algebraic generalization of convex polytopes. Introduced as ...
    • Weak Expansiveness for Actions of Sofic Groups 

      [OWP-2014-05] Chung, Nhan-Phu; Zhang, Guohua (Mathematisches Forschungsinstitut Oberwolfach, 2014-04-25)
      In this paper, we shall introduce h-expansiveness and asymptotical h-expansiveness for actions of sofic groups. By the definitions, each h-expansive action of sofic groups is asymptotically h-expansive. We show that ...
    • Weak*-Continuity of Invariant Means on Spaces of Matrix Coefficients 

      [OWP-2021-08] de Laat, Tim; Zadeh, Safoura (Mathematisches Forschungsinstitut Oberwolfach, 2021-07-13)
      With every locally compact group G, one can associate several interesting bi-invariant subspaces X(G) of the weakly almost periodic functions WAP(G) on G, each of which captures parts of the representation ...
    • Weak-duality based adaptive finite element methods for PDE-constrained optimization with pointwise gradient state-constraints 

      [OWP-2010-15] Hintermüller, Michael; Hinze, Michael; Hoppe, Ronald H. W. (Mathematisches Forschungsinstitut Oberwolfach, 2010)
      Adaptive finite element methods for optimization problems for second order linear elliptic partial di erential equations subject to pointwise constraints on the 2-norm of the gradient of the state are considered. ...
    • Weakly Complex Homogeneous Spaces 

      [OWP-2012-04] Moroianu, Andrei; Semmelmann, Uwe (Mathematisches Forschungsinstitut Oberwolfach, 2012-04-24)
      We complete our recent classification of compact inner symmetric spaces with weakly complex tangent bundle by filling up a case which was left open, and extend this classification to the larger category of compact homogeneous ...
    • Weighted Fourier inequalities for radial functions 

      [OWP-2009-26] Gorbachev, D.; Liflyand, E.; Tichonovič, S. V. (Mathematisches Forschungsinstitut Oberwolfach, 2009-03-19)
      Weighted Lp(Rn)Lq(Rn) Fourier inequalities are studied. We prove Pitt-Boas type results on integrability with power weights of the Fourier transform of a radial function.
    • Weighted Surface Algebras: General Version 

      [OWP-2019-07] Erdmann, Karin; Skowroński, Andrzej (Mathematisches Forschungsinstitut Oberwolfach, 2019-02-28)
      We introduce general weighted surface algebras of triangulated surfaces with arbitrarily oriented triangles and describe their basic properties. In particular, we prove that all these algebras, except the singular disc, ...
    • A Well-Posedness Result for Viscous Compressible Fluids with Only Bounded Density 

      [OWP-2018-10] Danchin, Raphaël; Fanelli, Francesco; Paicu, Marius (Mathematisches Forschungsinstitut Oberwolfach, 2018-05-28)
      We are concerned with the existence and uniqueness of solutions with only bounded density for the barotropic compressible Navier-Stokes equations. Assuming that the initial velocity has slightly sub-critical regularity and ...
    • The Weyl group of the Cuntz algebra 

      [OWP-2011-31] Conti, Roberto; Hong, Jeong Hee; Szymański, Wojciech (Mathematisches Forschungsinstitut Oberwolfach, 2011-05-28)
      The Weyl group of the Cuntz algebra On is investigated. This is (isomorphic to) the group of polynomial automorphisms λu of On, namely those induced by unitaries u that can be written ...
    • Weyl-Titchmarsh Functions of Vector-Valued Sturm-Liouville Operators on the Unit Interval 

      [OWP-2008-13] Chelkak, Dmitry; Korotyaev, Evgeny (Mathematisches Forschungsinstitut Oberwolfach, 2008)
      The matrix-valued Weyl-Titchmarsh functions M(λ) of vector-valued Sturm-Liouville operators on the unit interval with the Dirichlet boundary conditions are considered. The collection of the eigenvalues (i.e., poles ...
    • When Alcoved Polytopes Add 

      [OWP-2025-04] Early, Nick; Kühne, Lukas; Monin, Leonid (Mathematisches Forschungsinstitut Oberwolfach, 2025-04)
      Alcoved polytopes are characterized by the property that all facet normal directions are parallel to the roots eiej. Unlike other prominent families of polytopes, like generalized permutahedra, alcoved polytopes are ...
    • Yet another algorithm for the symmetric eigenvalue problem 

      [OWP-2016-02] Aurentz, Jared L.; Mach, Thomas; Vandebril, Raf; Watkins, David S. (Mathematisches Forschungsinstitut Oberwolfach, 2016-05-10)
      In this paper we present a new algorithm for solving the symmetric matrix eigenvalue problem that works by first using a Cayley transformation to convert the symmetric matrix into a unitary one and then uses Gragg’s ...
    • Z2-Thurston Norm and Complexity of 3-Manifolds, II 

      [OWP-2017-36] Jaco, William; Rubinstein, J. Hyam; Spreer, Jonathan; Tillmann, Stephan (Mathematisches Forschungsinstitut Oberwolfach, 2017-12-20)
      In this sequel to earlier papers by three of the authors, we obtain a new bound on the complexity of a closed 3-manifold, as well as a characterisation of manifolds realising our complexity bounds. As an application, we ...
    • Zeta functions of 3-dimensional p-adic Lie algebras 

      [OWP-2007-10] Klopsch, Benjamin; Voll, Christopher (Mathematisches Forschungsinstitut Oberwolfach, 2007-03-26)
      We give an explicit formula for the subalgebra zeta function of a general 3-dimensional Lie algebra over the p-adic integers Zp. To this end, we associate to such a Lie algebra a ternary quadratic form over ...