Now showing items 1-20 of 36

• #### Z2-Thurston Norm and Complexity of 3-Manifolds, II ﻿

[OWP-2017-36] (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 ...
• #### Gradient Canyons, Concentration of Curvature, and Lipschitz Invariants ﻿

[OWP-2017-35] (Mathematisches Forschungsinstitut Oberwolfach, 2017-12-13)
We find new bi-Lipschitz invariants of holomorphic functions of two variables by using the gradient canyons and by combining analytic and geometric viewpoints on the concentration of curvature.
• #### Bredon Cohomology and Robot Motion Planning ﻿

[OWP-2017-34] (Mathematisches Forschungsinstitut Oberwolfach, 2017-11-29)
In this paper we study the topological invariant ${\sf {TC}}(X)$ reflecting the complexity of algorithms for autonomous robot motion. Here, $X$ stands for the configuration space of a system and ${\sf {TC}}(X)$ is, roughly, ...
• #### Experimenting with Zariski Dense Subgroups ﻿

[OWP-2017-31] (Mathematisches Forschungsinstitut Oberwolfach, 2017-10-28)
We give a method to describe all congruence images of a finitely generated Zariski dense group $H\leq SL(n, \mathbb{R})$. The method is applied to obtain efficient algorithms for solving this problem in odd prime degree ...
• #### The Varchenko Determinant of a Coxeter Arrangement ﻿

[OWP-2017-33] (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 ...
• #### Looking Back on Inverse Scattering Theory ﻿

[OWP-2017-24] (Mathematisches Forschungsinstitut Oberwolfach, 2017-10-05)
We present an essay on the mathematical development of inverse scattering theory for time-harmonic waves during the past fifty years together with some personal memories of our participation in these events.
• #### GAP Functionality for Zariski Dense Groups ﻿

[OWP-2017-22] (Mathematisches Forschungsinstitut Oberwolfach, 2017-09-14)
In this document we describe the functionality of GAP [4] routines for Zariski dense or arithmetic groups that are developed in [1, 2, 3]. The research underlying the software was supported through the programme "Research ...
• #### Geometry of Free Loci and Factorization of Noncommutative Polynomials ﻿

[OWP-2017-23] (Mathematisches Forschungsinstitut Oberwolfach, 2017-10-02)
The free singularity locus of a noncommutative polynomial f is defined to be the sequence $Z_n(f)=\{X\in M_n^g : \det f(X)=0\}$ of hypersurfaces. The main theorem of this article shows that f is irreducible if and only if ...
• #### Composition of Irreducible Morphisms in Coils ﻿

[OWP-2017-32] (Mathematisches Forschungsinstitut Oberwolfach, 2017-10-30)
We study the non-zero composition of n irreducible morphisms between modules lying in coils in relation with the powers of the radical of their module category.
• #### Non-Extendability of Holomorphic Functions with Bounded or Continuously Extendable Derivatives ﻿

[OWP-2017-30] (Mathematisches Forschungsinstitut Oberwolfach, 2017-10-21)
• #### An Extension Problem and Trace Hardy Inequality for the Sublaplacian on H-Type Groups ﻿

[OWP-2017-20] (Mathematisches Forschungsinstitut Oberwolfach, 2017-07-24)
In this paper we study the extension problem for the sublaplacian on a H-type group and use the solutions to prove trace Hardy and Hardy inequalities for fractional powers of the sublaplacian.
• #### Counting Curves on Toric Surfaces Tropical Geometry & the Fock Space ﻿

[OWP-2017-18] (Mathematisches Forschungsinstitut Oberwolfach, 2017-07-17)
We study the stationary descendant Gromov–Witten theory of toric surfaces by combining and extending a range of techniques – tropical curves, floor diagrams, and Fock spaces. A correspondence theorem is established between ...
• #### The Pseudo-Hyperresolution and Applications ﻿

[OWP-2017-17] (Mathematisches Forschungsinstitut Oberwolfach, 2017-07-04)
Resolving objects in an abelian category by injective (projective) resolutions is a fundamental problem in mathematics, and this article aims at introducing a particular solution called “Pseudo-hyperresolutions”. This ...
• #### Matrix Elements of Irreducible Representations of SU(n+1) x SU(n+1) and Multivariable Matrix-Valued Orthogonal Polynomials ﻿

[OWP-2017-16] (Mathematisches Forschungsinstitut Oberwolfach, 2017-06-14)
In Part 1 we study the spherical functions on compact symmetric pairs of arbitrary rank under a suitable multiplicity freeness assumption and additional conditions on the branching rules. The spherical functions are ...