Browsing 1  Oberwolfach Preprints (OWP) by Issue Date
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Drawing large pictures at random : Oberwolfach Lecture 2007
[OWP200708] (Mathematisches Forschungsinstitut Oberwolfach, 2007)This lecture is of very introductory nature. The goal will be to describe specific concrete questions, and to use them as a tool to convey some general ideas. Let me therefore skip the general introduction and immediately ... 
Geometric flows and 3manifolds : Oberwolfach Lecture 2005
[OWP200701] (Mathematisches Forschungsinstitut Oberwolfach, 2007)The current article arose from a lecture1 given by the author in October 2005 on the work of R. Hamilton and G. Perelman on Ricciflow and explains central analytical ingredients in geometric parabolic evolution equations ... 
The McKayconjecture for exceptional groups and odd primes
[OWP200707] (Mathematisches Forschungsinstitut Oberwolfach, 2007)Let $\mathbf{G}$ be a simplyconnected simple algebraic group over an algebraically closed field of characteristic p with a Frobenius map $F:\mathbf{G}→\mathbf{G}$ and $\mathbf{G}:=\mathbf{G}^F$, such that the root system ... 
A 3local identification of the alternating group of degree 8, the McLaughlin simple group and their automorphism groups
[OWP200702] (Mathematisches Forschungsinstitut Oberwolfach, 20070320)In this article we give 3local characterizations of the alternating and symmetric groups of degree 8 and use these characterizations to recognize the sporadic simple group discovered by McLaughlin from its 3local subgroups. 
Resolution of symplectic cyclic orbifold singularities
[OWP200703] (Mathematisches Forschungsinstitut Oberwolfach, 20070321)In this paper we present a method to obtain resolutions of symplectic orbifolds arising as quotients of presymplectic semifree S1actions. This includes, in particular, all orbifolds arising from symplectic reduction of ... 
Vector bundles on degenerations of elliptic curves and YangBaxter equations
[OWP200704] (Mathematisches Forschungsinstitut Oberwolfach, 20070322)In this paper we introduce the notion of a gemetric associative rmatrix attached to a genus one fibration with a section and irreducible fibres. It allows us to study degenerations of solutions of the classical YangBaxter ... 
On test sets for nonlinear integer maximization
[OWP200705] (Mathematisches Forschungsinstitut Oberwolfach, 20070323)A finite test set for an integer maximation problem enables us to verify whether a feasible point atains the global maximum. We establish in this paper several general results that apply to integer maximization problems ... 
Nonlinear matroid optimization and experimental design
[OWP200706] (Mathematisches Forschungsinstitut Oberwolfach, 20070324)We study the problem of optimizing nonlinear objective functions over matroids presented by oracles or explicitly. Such functions can be interpreted as the balancing of multicriteria optimization. We provide a combinatorial ... 
Selfdual polygons and selfdual curves
[OWP200709] (Mathematisches Forschungsinstitut Oberwolfach, 20070325) 
Zeta functions of 3dimensional padic Lie algebras
[OWP200710] (Mathematisches Forschungsinstitut Oberwolfach, 20070326)We give an explicit formula for the subalgebra zeta function of a general 3dimensional Lie algebra over the $p$adic integers $\mathbb{Z}_p$. To this end, we associate to such a Lie algebra a ternary quadratic form over ... 
Secondary heat flow between confocal ellipses: an application of extended thermodynamics
[OWP200711] (Mathematisches Forschungsinstitut Oberwolfach, 20070327)Much as nonNewtonian fluids exhibit secondary flows in elliptic pipes, rarefied gases exhibit secondary heat flows between elliptical cylinders. The phenomenon may be called nonFourierian, because it is not covered by ... 
Slowly oscillating wave solutions of a single species reactiondiffusion equation with delay
[OWP200712] (Mathematisches Forschungsinstitut Oberwolfach, 20070328)We study positive bounded wave solutions $u(t, x) = \phi(\nu \cdot x+ct)$, $\phi(\infty)=0$, of equation $u_t(t, x)=\delta u(t,x)−u(t,x) +g(u(t−h,x))$, $x \in \mathbb{R}^m$(*). It is supposed that Eq. (∗) has exactly two ... 
HölderDifferentiability of Gibbs Distribution Functions
[OWP200713] (Mathematisches Forschungsinstitut Oberwolfach, 20070329)In this paper we give nontrivial applications of the thermodynamic formalism to the theory of distribution functions of Gibbs measures (devil’s staircases) supported on limit sets of finitely generated conformal iterated ... 
A note on k[z]Automorphisms in Two Variables
[OWP200817] (Mathematisches Forschungsinstitut Oberwolfach, 2008)We prove that for a polynomial $f \in k[x, y, z]$ equivalent are: (1)$f$ is a $k[z]$coordinate of $k[z][x,y]$, and (2) $k[x, y, z]/(f)\cong k^[2]$ and $f(x,y,a)$ is a coordinate in $k[x,y]$ for some $a \in k$. This solves ... 
On the Directionally Newtonnondegenerate Singularities of Complex Hypersurfaces
[OWP200816] (Mathematisches Forschungsinstitut Oberwolfach, 2008)We introduce a minimal generalization of Newtonnondegenerate singularities of hypersurfaces. Roughly speaking, an isolated hypersurface singularity is called directionally Newtonnondegenerate if the local embedded ... 
On the δ=const Collisions of Singularities of Complex Plane Curves
[OWP200815] (Mathematisches Forschungsinstitut Oberwolfach, 2008)We study a specific class of deformations of curve singularities: the case when the singular point splits to several ones, such that the total $\delta$ invariant is preserved. These are also known as equinormalizable or ... 
WeylTitchmarsh Functions of VectorValued SturmLiouville Operators on the Unit Interval
[OWP200813] (Mathematisches Forschungsinstitut Oberwolfach, 2008)The matrixvalued WeylTitchmarsh functions $M(\lambda)$ of vectorvalued SturmLiouville operators on the unit interval with the Dirichlet boundary conditions are considered. The collection of the eigenvalues (i.e., poles ... 
Formal punctured ribbons and twodimensional local fields
[OWP200801] (Mathematisches Forschungsinstitut Oberwolfach, 20080305)We investigate formal ribbons on curves. Roughly speaking, formal ribbon is a family of locally linearly compact vector spaces on a curve. We establish a onetoone correspondence between formal ribbons on curves plus some ... 
Upper tails for intersection local times of random walks in supercritical dimensions
[OWP200802] (Mathematisches Forschungsinstitut Oberwolfach, 20080306)We determine the precise asymptotics of the logarithmic upper tail probability of the total intersection local time of $p$ independent random walks in $\mathbb{Z}^d$ under the assumption $p(d2)>d$. Our approach allows a ... 
Hecke duality relations of Jacobi forms
[OWP200803] (Mathematisches Forschungsinstitut Oberwolfach, 20080307)In this paper we introduce a new subspace of Jacobi forms of higher degree via certain relations among Fourier coefficients. We prove that this space can also be characterized by duality properties of certain distinguished ...