• 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 ...
    • A Generalization of the Discrete Version of Minkowski’s Fundamental Theorem 

      [OWP-2014-17] González Merino, Bernardo; Henze, Matthias (Mathematisches Forschungsinstitut Oberwolfach, 2014)
      One of the most fruitful results from Minkowski’s geometric viewpoint on number theory is his so called 1st Fundamental Theorem. It provides an optimal upper bound for the volume of an o-symmetric convex body whose only ...
    • Holomorphic automorphic forms and cohomology 

      [OWP-2014-07] Bruggeman, Roelof W.; Ch'oe, Yŏng-ju; Diamantis, Nikolaos (Mathematisches Forschungsinstitut Oberwolfach, 2014-04-25)
      We investigate the correspondence between holomorphic automorphic forms on the upper half-plane with complex weight and parabolic cocycles. For integral weights at least 2 this correspondence is given by the Eichler integral. ...
    • The Magic Square of Reflections and Rotations 

      [OWP-2018-13] Buchweitz, Ragnar-Olaf; Faber, Eleonore; Ingalls, Colin (Mathematisches Forschungsinstitut Oberwolfach, 2018-07-01)
      We show how Coxeter’s work implies a bijection between complex reflection groups of rank two and real reflection groups in 0(3). We also consider this magic square of reflections and rotations in the framework of Clifford ...
    • On an Effective Variation of Kronecker’s Approximation Theorem Avoiding Algebraic Sets 

      [OWP-2017-28] Fukshansky, Lenny; German, Oleg; Moshchevitin, Nikolay (Mathematisches Forschungsinstitut Oberwolfach, 2017-10-19)
      Let $\Lambda \subset \mathbb R^n$ be an algebraic lattice, coming from a projective module over the ring of integers of a number field $K$. Let $\mathcal Z \subset \mathbb R^n$ be the zero locus of a finite collection of ...
    • Plethysms, replicated Schur functions and series, with applications to vertex operators 

      [OWP-2010-12] Fauser, Bertfried; Jarvis, Peter D.; King, Ronald C. (Mathematisches Forschungsinstitut Oberwolfach, 2010-03-14)
      Specializations of Schur functions are exploited to define and evaluate the Schur functions $s_\lambda [\alpha X]$ and plethysms $s_\lambda [\alpha s_\nu(X))]$ for any $\alpha$-integer, real or complex. Plethysms are then ...
    • Positive Margins and Primary Decomposition 

      [OWP-2012-06] Kahle, Thomas; Rauh, Johannes; Sullivant, Seth (Mathematisches Forschungsinstitut Oberwolfach, 2012)
      We study random walks on contingency tables with fixed marginals, corresponding to a (log-linear) hierarchical model. If the set of allowed moves is not a Markov basis, then there exist tables with the same marginals that ...
    • Products of pairs of Dehn twists and maximal real Lefschetz fibrations 

      [OWP-2011-32] Degtyarev, Alex; Salepci, Nermin (Mathematisches Forschungsinstitut Oberwolfach, 2011)
      We address the problem of existence and uniqueness of a factorization of a given element of the modular group into a product of two Dehn twists. As a geometric application, we conclude that any maximal real elliptic ...
    • A series of algebras generalizing the Octonions and Hurwitz-Radon Identity 

      [OWP-2010-10] Morier-Genoud, Sophie; Ovsienko, Valentin (Mathematisches Forschungsinstitut Oberwolfach, 2010)
      We study non-associative twisted group algebras over $(\mathbb{Z}_2)^n$ with cubic twisting functions. We construct a series of algebras that extend the classical algebra of octonions in the same way as the Clifford algebras ...
    • Supertropical linear algebra 

      [OWP-2010-14] Izhakian, Zur; Knebusch, Manfred; Rowen, Louis (Mathematisches Forschungsinstitut Oberwolfach, 2010)
      The objective of this paper is to lay out the algebraic theory of supertropical vector spaces and linear algebra, utilizing the key antisymmetric relation of "ghost surpasses." Special attention is paid to the various ...
    • Supertropical Quadratic Forms I 

      [OWP-2013-27] Knebusch, Manfred; Rowen, Louis; Izhakian, Zur (Mathematisches Forschungsinstitut Oberwolfach, 2013)
      We initiate the theory of a quadratic form q over a semiring $R$. As customary, one can write $q(x+y)=q(x)+q(y)+b(x,y)$, where b is a companion bilinear form. But in contrast to the ring-theoretic case, the companion ...
    • 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 $\mathbb{Z}_p$. To this end, we associate to such a Lie algebra a ternary quadratic form over ...