• Equidistribution of Elements of Norm 1 in Cyclic Extensions 

      [OWP-2014-14] Petersen, Kathleen L.; Sinclair, Christopher D. (Mathematisches Forschungsinstitut Oberwolfach, 2014-08-20)
      Upon quotienting by units, the elements of norm 1 in a number field $K$ form a countable subset of a torus of dimension $r_1+r_2-1$ where $r_1$ are the numbers of real and pairs of complex embeddings. When $K$ is Galois ...
    • Euler Reflexion Formulas for Motivic Multiple Zeta Functions 

      [OWP-2015-17] Thuong, Lê Quy; Nguyen, Hong Duc (Mathematisches Forschungsinstitut Oberwolfach, 2015-11-18)
      We introduce a new notion of *-product of two integrable series with coeficients in distinct Grothendieck rings of algebraic varieties, preserving the integrability and commuting with the limit of rational series. In the ...
    • Even-homogeneous supermanifolds on the complex projective line 

      [OWP-2013-02] Vishnyakova, E. G. (Mathematisches Forschungsinstitut Oberwolfach, 2013-03-14)
      The classification of even-homogeneous complex supermanifolds of dimension $1|m$, $m<=3$, on $\mathbb{CP}^1$ up to isomorphism is given. An explicit description of such supermanifolds in terms of local charts and coordinates ...
    • Exact Rate of Convergence of k-Nearest-Neighbor Classification Rule 

      [OWP-2017-25] Györfi, László; Döring, Maik; Walk, Harro (Mathematisches Forschungsinstitut Oberwolfach, 2017-10-16)
      A binary classification problem is considered. The excess error probability of the k-nearest neighbor classification rule according to the error probability of the Bayes decision is revisited by a decomposition of the ...
    • Exceptional Legendrian Torus Knots 

      [OWP-2018-04] Geiges, Hansjörg; Onaran, Sinem (Mathematisches Forschungsinstitut Oberwolfach, 2018-03-21)
      We present classification results for exceptional Legendrian realisations of torus knots. These are the first results of that kind for non-trivial topological knot types. Enumeration results of Ding-Li-Zhang concerning ...
    • Experimenting with Symplectic Hypergeometric Monodromy Groups 

      [OWP-2019-15] Detinko, Alla; Flannery, Dane; Hulpke, Alexander (Mathematisches Forschungsinstitut Oberwolfach, 2019-05-22)
      We present new computational results for symplectic monodromy groups of hypergeometric differential equations. In particular, we compute the arithmetic closure of each group, sometimes justifying arithmeticity. The results ...
    • Experimenting with Zariski Dense Subgroups 

      [OWP-2017-31] Detinko, Alla; Flannery, Dane; Hulpke, Alexander (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 ...
    • An Explicit Formula for the Dirac Multiplicities on Lens Spaces 

      [OWP-2014-19] Boldt, Sebastian; Lauret, Emilio A. (Mathematisches Forschungsinstitut Oberwolfach, 2014)
      We present a new description of the spectrum of the (spin-) Dirac operator $D$ on lens spaces. Viewing a spin lens space $L$ as a locally symmetric space $\Gamma \setminus Spin(2m)/Spin(2m-1)$ and exploiting the representation ...
    • An Extension Problem and Trace Hardy Inequality for the Sublaplacian on H-Type Groups 

      [OWP-2017-20] Roncal, Luz; Thangavelu, Sundaram (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.
    • Extremal configurations of polygonal linkages 

      [OWP-2011-24] Khimshiashvili, Giorgi; Panina, Gaiane; Siersma, Dirk; Zhukova, Alena (Mathematisches Forschungsinstitut Oberwolfach, 2011-05-22)
    • Fibonacci-like unimodal inverse limit spaces 

      [OWP-2010-03] Bruin, H.; Štimac, S. (Mathematisches Forschungsinstitut Oberwolfach, 2010-03-9)
      We study the structure of inverse limit space of so-called Fibonacci-like tent maps. The combinatorial constraints implied by the Fibonacci-like assumption allows us to introduce certain chains that enable a more detailed ...
    • Finitary Proof Systems for Kozen's μ 

      [OWP-2016-26] Afshari, Bahareh; Leigh, Graham E. (Mathematisches Forschungsinstitut Oberwolfach, 2016-12-30)
      We present three finitary cut-free sequent calculi for the modal $μ$-calculus. Two of these derive annotated sequents in the style of Stirling’s ‘tableau proof system with names’ (2014) and feature special inferences that ...
    • The First Hochschild Cohomology as a Lie Algebra 

      [OWP-2019-09] Rubio y Degrassi, Lleonard; Schroll, Sibylle; Solotar, Andrea (Mathematisches Forschungsinstitut Oberwolfach, 2019-04-16)
      In this paper we study sufficient conditions for the solvability of the first Hochschild cohomology of a finite dimensional algebra as a Lie algebra in terms of its Ext-quiver in arbitrary characteristic. In particular, ...
    • Formal adjoints of linear DAE operators and their role in optimal control 

      [OWP-2011-15] Kunkel, Peter; Mehrmann, Volker (Mathematisches Forschungsinstitut Oberwolfach, 2011-05-16)
      For regular strangeness-free linear differential-algebraic equations (DAEs) the definition of an adjoint DAE is straightforward. This definition can be formally extended to general linear DAEs. In this paper, we analyze ...
    • Formal punctured ribbons and two-dimensional local fields 

      [OWP-2008-01] Kurke, Herbert; Osipov, Denis; Zheglov, Alexander (Mathematisches Forschungsinstitut Oberwolfach, 2008-03-05)
      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 one-to-one correspondence between formal ribbons on curves plus some ...
    • The Fourier Transform on Harmonic Manifolds of Purely Exponential Volume Growth 

      [OWP-2019-12] Biswas, Kingshook; Knieper, Gerhard; Peyerimhoff, Norbert (Mathematisches Forschungsinstitut Oberwolfach, 2019-05-08)
      Let $X$ be a complete, simply connected harmonic manifold of purely exponential volume growth. This class contains all non-flat harmonic manifolds of non-positive curvature and, in particular all known examples of harmonic ...
    • Fourier-Mukai transform on Weierstrass cubics and commuting differential operators 

      [OWP-2016-03] Burban, Igor; Zheglov, Alexander (Mathematisches Forschungsinstitut Oberwolfach, 2016-05-10)
      In this article, we describe the spectral sheaves of algebras of commuting differential operators of genus one and rank two with singular spectral curve, solving a problem posed by Previato and Wilson. We also classify all ...
    • Freeness of Multi-Reflection Arrangements via Primitive Vector Fields 

      [OWP-2017-10] Hoge, Torsten; Mano, Toshiyuki; Röhrle, Gerhard; Stump, Christian (Mathematisches Forschungsinstitut Oberwolfach, 2017-04-20)
      In 2002, Terao showed that every reflection multi-arrangement of a real reflection group with constant multiplicity is free by providing a basis of the module of derivations. We first generalize Terao's result to ...
    • A Function Algebra Providing New Mergelyan Type Theorems in Several Complex Variables 

      [OWP-2019-02] Falcó, Javier; Gauthier, Paul Montpetit; Manolaki, Myrto; Nestoridis, Vassili (Mathematisches Forschungsinstitut Oberwolfach, 2019-02-11)
      For compact sets $K\subset \mathbb C^{d}$, we introduce a subalgebra $A_{D}(K)$ of $A(K)$, which allows us to obtain Mergelyan type theorems for products of planar compact sets as well as for graphs of functions.
    • Fundamental Theorem of Projective Geometry over Semirings 

      [OWP-2021-09] Tewari, Ayush Kumar (Mathematisches Forschungsinstitut Oberwolfach, 2021-10-11)
      We state the fundamental theorem of projective geometry for semimodules over semirings, which is facilitated by recent work in the study of bases in semimodules defined over semirings. In the process we explore in detail ...