Browsing 1 - Oberwolfach Preprints (OWP) by Title

Now showing items 203-222 of 399

    • Minimal Codimension One Foliation of a Symmetric Space by Damek-Ricci Spaces 

      [OWP-2019-11] Knieper, Gerhard; Parker, John R.; Peyerimhoff, Norbert (Mathematisches Forschungsinstitut Oberwolfach, 2019-05-07)
      In this article we consider solvable hypersurfaces of the form $N \exp(\mathbb{R} H)$ with induced metrics in the symmetric space $M = SL(3,\mathbb{C})/SU(3)$, where $H$ a suitable unit length vector in the subgroup $A$ ...

    • The Minimal Resolution Conjecture on a general quartic surface in $\mathbb P^3$ 

      [OWP-2017-21] Boij, Mats; Migliore, Juan; Miró-Roig, Rosa M.; Nagel, Uwe (Mathematisches Forschungsinstitut Oberwolfach, 2017-07-27)
      Mustaţă has given a conjecture for the graded Betti numbers in the minimal free resolution of the ideal of a general set of points on an irreducible projective algebraic variety. For surfaces in $\mathbb P^3$ this conjecture ...

    • Minimal Riesz energy on the sphere for axis-supported external fields 

      [OWP-2009-04] Brauchart, Johann S.; Dragnev, Peter D.; Saff, Edward B. (Mathematisches Forschungsinstitut Oberwolfach, 2009)
      Abstract. We investigate the minimal Riesz $s$-energy problem for positive measures on the d-dimensional unit sphere $\mathbb{S}^d$ in the presence of an external field induced by a point charge, and more generally by ...

    • Module Categories for Group Algebras over Commutative Rings 

      [OWP-2012-12] Benson, David J.; Iyengar, Srikanth B.; Krause, Henning; Stevenson, Greg (Mathematisches Forschungsinstitut Oberwolfach, 2012-10-01)
      We develop a suitable version of the stable module category of a finite group $G$ over an arbitrary commutative ring $k$. The purpose of the construction is to produce a compactly generated triangulated category whose ...

    • Monoid valuations and value ordered supervaluations 

      [OWP-2011-17] Izhakian, Zur; Knebusch, Manfred; Rowen, Louis (Mathematisches Forschungsinstitut Oberwolfach, 2011)
      We complement two papers on supertropical valuation theory ([IKR1], [IKR2]) by providing natural examples of m-valuations (= monoid valuations), after that of supervaluations and transmissions between them. The supervaluations ...

    • MOSES: A Streaming Algorithm for Linear Dimensionality Reduction 

      [OWP-2018-12] Eftekhari, Armin; Hauser, Raphael A.; Grammenos, Andreas (Mathematisches Forschungsinstitut Oberwolfach, 2018-06-26)
      This paper introduces Memory-limited Online Subspace Estimation Scheme (MOSES) for both estimating the principal components of data and reducing its dimension. More specifically, consider a scenario where the data vectors ...

    • Multi-Dimensional Summation-by-Parts Operators for General Function Spaces: Theory and Construction 

      [OWP-2023-13] Glaubitz, Jan; Klein, Simon-Christian; Nordström, Jan; Öffner, Philipp (Mathematisches Forschungsinstitut Oberwolfach, 2023-07-25)
      Summation-by-parts (SBP) operators allow us to systematically develop energy-stable and high-order accurate numerical methods for time-dependent differential equations. Until recently, the main idea behind existing SBP ...

    • Multiple Bernoulli series and volumes of moduli spaces of flat bundles over surfaces 

      [OWP-2013-04] Baldoni, Maria Welleda; Boysal, Arzu; Vergne, Michèle (Mathematisches Forschungsinstitut Oberwolfach, 2013-03-14)
      Using Szenes formula for multiple Bernoulli series, we explain how to compute Witten series associated to classical Lie algebras. Particular instances of these series compute volumes of moduli spaces of flat bundles over ...

    • Multivariate Hybrid Orthogonal Functions 

      [OWP-2020-04] Bracciali, Cleonice F.; Pérez, Teresa E. (Mathematisches Forschungsinstitut Oberwolfach, 2020-03-12)
      We consider multivariate orthogonal functions satisfying hybrid orthogonality conditions with respect to a moment functional. This kind of orthogonality means that the product of functions of different parity order ...

    • The Nagata automorphism is shifted linearizable 

      [OWP-2008-09] Maubach, Stefan; Poloni, Pierre-Marie (Mathematisches Forschungsinstitut Oberwolfach, 2008-03-13)
      A polynomial automorphism $F$ is called shifted linearizable if there exists a linear map $L$ such that $LF$ is linearizable. We prove that the Nagata automorphism $N:= (X-Y\Delta-Z\Delta^2,Y+Z\Delta,Z)$ where $\Delta=XZ+Y^2$ ...

    • Near critical density irregular sampling in bernstein spaces 

      [OWP-2013-16] Olevskij, Aleksandr M.; Ulanovskii, Alexander (Mathematisches Forschungsinstitut Oberwolfach, 2013-07-23)
      We obtain sharp estimates for the sampling constants in Bernstein spaces when the density of the sampling set is near the critical value.

    • A nested family of k-total effective rewards for positional games 

      [OWP-2015-21] Boros, Endre; Elbassioni, Khaled; Gurvich, Vladimir; Makino, Kazuhisa (Mathematisches Forschungsinstitut Oberwolfach, 2015)
      We consider Gillette's two-person zero-sum stochastic games with perfect information. For each $k \in \mathbb{Z}_+$ we introduce an effective reward function, called $k$-total. For $k = 0$ and $1$ this function is known ...

    • A new counting function for the zeros of holomorphic curves 

      [OWP-2009-25] Anderson, J. M.; Hinkkanen, Aimo (Mathematisches Forschungsinstitut Oberwolfach, 2009-03-18)
      Let $f_1,..., f_p$ be entire functions that do not all vanish at any point, so that $(f_1,..., f_p)$ is a holomorphic curve in $\mathbb{CP}^{p-1}$. We introduce a new and more careful notion of counting the order of the ...

    • New representations of matroids and generalizations 

      [OWP-2011-18] Izhakian, Zur; Rhodes, John L. (Mathematisches Forschungsinstitut Oberwolfach, 2011)
      We extend the notion of matroid representations by matrices over fields by considering new representations of matroids by matrices over finite semirings, more precisely over the boolean and the superboolean semirings. This ...

    • Non-Extendability of Holomorphic Functions with Bounded or Continuously Extendable Derivatives 

      [OWP-2017-30] Moschonas, Dionysios; Nestoridis, Vassili (Mathematisches Forschungsinstitut Oberwolfach, 2017-10-21)
      We consider the spaces $H_{F}^{\infty}(\Omega)$ and $\mathcal{A}_{F}(\Omega)$ containing all holomorphic functions $f$ on an open set $\Omega \subseteq \mathbb{C}$, such that all derivatives $f^{(l)}$, $l\in F \subseteq ...

    • Non-integrated defect relation for meromorphic maps of complete Kähler manifolds into a projective variety intersecting hypersurfaces 

      [OWP-2010-19] Tran, Van Tan; Vu, Van Truong (Mathematisches Forschungsinstitut Oberwolfach, 2010)
      In 1985, Fujimoto established a non-integrated defect relation for meromorphic maps of complete Kähler manifolds into the complex projective space intersecting hyperplanes in general position. In this paper, we generalize ...

    • Non-Standard Behavior of Density Estimators for Sums of Squared Observations 

      [OWP-2008-07] Schick, Anton; Wefelmeyer, Wolfgang (Mathematisches Forschungsinstitut Oberwolfach, 2008-03-11)
      It has been shown recently that, under an appropriate integrability condition, densities of functions of independent and identically distributed random variables can be estimated at the parametric rate by a local U-statistic, ...

    • Non-stationary multivariate subdivision: joint spectral radius and asymptotic similarity 

      [OWP-2013-20] Charina, Maria; Conti, Costanza; Guglielmi, Nicola; Protasov, Vladimir (Mathematisches Forschungsinstitut Oberwolfach, 2013-10-29)
      In this paper we study scalar multivariate non-stationary subdivision schemes with a general integer dilation matrix. We present a new numerically efficient method for checking convergence and Hölder ...

    • Noncommutative Marked Surfaces 

      [OWP-2015-16] Berenstein, Arkady; Retakh, Vladimir (Mathematisches Forschungsinstitut Oberwolfach, 2015-11-18)
      The aim of the paper is to attach a noncommutative cluster-like structure to each marked surface $\Sigma$. This is a noncommutative algebra $\mathcal{A}_\Sigma$ generated by “noncommutative geodesics” between marked points ...

    • Noncommutative topological entropy of endomorphismus of Cuntz Algebras 

      [OWP-2008-12] Skalski, Adam; Zacharias, Joachim (Mathematisches Forschungsinstitut Oberwolfach, 2008-03-16)
      Noncommutative topological entropy estimates are obtained for ‘finite range’ endomorphisms of Cuntz algebras,generalising known results for the canonical shift endomorphisms. Exact values are computed for a class of ...