Now showing items 1881-1900 of 1987

    • Bounded Weight Modules for Basic Classical Lie Superalgebras at Infinity 

      [OWP-2022-09] Grantcharov, Dimitar; Penkov, Ivan; Serganova, Vera (Mathematisches Forschungsinstitut Oberwolfach, 2022-05-30)
      We classify simple bounded weight modules over the complex simple Lie superalgebras $\mathfrak{sl}(\infty |\infty)$ and $\mathfrak{osp} (m | 2n)$, when at least one of $m$ and $n$ equals $\infty$. For $\mathfrak{osp} (m | ...
    • Jewellery from tessellations of hyperbolic space 

      [SNAP-2022-005-EN] Gangl, Herbert (Mathematisches Forschungsinstitut Oberwolfach, 2022-06-02)
      In this snapshot, we will first give an introduction to hyperbolic geometry and we will then show how certain matrix groups of a number-theoretic origin give rise to a large variety of interesting tessellations of 3-dimensional ...
    • Discretization of Inherent ODEs and the Geometric Integration of DAEs with Symmetries 

      [OWP-2022-10] Kunkel, Peter; Mehrmann, Volker (Mathematisches Forschungsinstitut Oberwolfach, 2022-06-08)
      Discretization methods for differential-algebraic equations (DAEs) are considered that are based on the integration of an associated inherent ordinary differential equation (ODE). This allows to make use of any discretization ...
    • On the Enumeration of Finite $L$-Algebras 

      [OWP-2022-11] Dietzel, Carsten; Menchón, Paula; Vendramin, Leandro (Mathematisches Forschungsinstitut Oberwolfach, 2022-06-29)
      We use Constraint Satisfaction Methods to construct and enumerate finite L-algebras up to isomorphism. These objects were recently introduced by Rump and appear in Garside theory, algebraic logic, and the study of the ...
    • Shock-avoiding Slicing Conditions: Tests and Calibrations 

      [OWP-2022-12] Baumgarte, Thomas W.; Hilditch, David (Mathematisches Forschungsinstitut Oberwolfach, 2022-07-19)
      While the 1+log slicing condition has been extremely successful in numerous numerical relativity simulations, it is also known to develop "gauge-shocks" in some examples. Alternative "shockavoiding" slicing conditions ...
    • Embedding Spaces of Split Links 

      [OWP-2022-13] Boyd, Rachael; Bregman, Corey (Mathematisches Forschungsinstitut Oberwolfach, 2022-08-01)
      We study the homotopy type of the space $\mathcal{E}(L)$ of unparametrised embeddings of a split link $L=L_1\sqcup \ldots \sqcup L_n$ in $\mathbb{R}^3$. Inspired by work of Brendle and Hatcher, we introduce a semi-simplicial ...
    • On a Conjecture of Khoroshkin and Tolstoy 

      [OWP-2022-14] Appel, Andrea; Gautam, Sachin; Wendlandt, Curtis (Mathematisches Forschungsinstitut Oberwolfach, 2022-08-02)
      We prove a no-go theorem on the factorization of the lower triangular part in the Gaussian decomposition of the Yangian's universal $R$-matrix, yielding a negative answer to a conjecture of Khoroshkin and Tolstoy from ...
    • Convergence and Error Analysis of Compressible Fluid Flows with Random Data: Monte Carlo Method 

      [OWP-2022-15] Feireisl, Eduard; Lukáčova-Medviďová, Mariá; She, Bangwei; Yuan, Yuhuan (Mathematisches Forschungsinstitut Oberwolfach, 2022-08-25)
      The goal of this paper is to study convergence and error estimates of the Monte Carlo method for the Navier-Stokes equations with random data. To discretize in space and time, the Monte Carlo method is combined with a ...
    • Solving inverse problems with Bayes' theorem 

      [SNAP-2022-006-EN] Latz, Jonas; Sprungk, Björn (Mathematisches Forschungsinstitut Oberwolfach, 2022-09-05)
      The goal of inverse problems is to find an unknown parameter based on noisy data. Such problems appear in a wide range of applications including geophysics, medicine, and chemistry. One method of solving them is known as ...
    • Root Cycles in Coxeter Groups 

      [OWP-2022-16] Hart, Sarah; Kelsey, Veronica; Rowley, Peter (Mathematisches Forschungsinstitut Oberwolfach, 2022-09-15)
      For an element $w$ of a Coxeter group $W$ there are two important attributes, namely its length, and its expression as a product of disjoint cycles in its action on $\Phi$, the root system of $W$. This paper investigates ...
    • Birational Rowmotion on a Rectangle over a Noncommutative Ring 

      [OWP-2022-17] Grinberg, Darij; Roby, Tom (Mathematisches Forschungsinstitut Oberwolfach, 2022-09-20)
      We extend the periodicity of birational rowmotion for rectangular posets to the case when the base field is replaced by a noncommutative ring (under appropriate conditions). This resolves a conjecture from 2014. The proof ...
    • Biological shape analysis with geometric statistics and learning 

      [SNAP-2022-008-EN] Utpala, Saiteja; Miolane, Nina (Mathematisches Forschungsinstitut Oberwolfach, 2022-10-25)
      The advances in biomedical imaging techniques have enabled us to access the 3D shapes of a variety of structures: organs, cells, proteins. Since biological shapes are related to physiological functions, shape data may hold ...
    • Representations and degenerations 

      [SNAP-2022-007-EN] Dumanski, Ilya; Kiritchenko, Valentina (Mathematisches Forschungsinstitut Oberwolfach, 2022-10-25)
      In this snapshot, we explain two important mathematical concepts (representation and degeneration) in elementary terms. We will focus on the simplest meaningful examples, and motivate both concepts by study of symmetry.
    • What is pattern? 

      [SNAP-2022-009-EN] Baake, Michael; Grimm, Uwe; Moody, Robert V. (Mathematisches Forschungsinstitut Oberwolfach, 2022-10-25)
      Pattern is ubiquitous and seems totally familiar. Yet if we ask what it is, we find a bewildering collection of answers. Here we suggest that there is a common thread, and it revolves around dynamics.
    • A tale of three curves 

      [SNAP-2022-010-EN] Balakrishnan, Jennifer S. (Mathematisches Forschungsinstitut Oberwolfach, 2022-10-27)
      In this snapshot, we give a survey of some problems in the study of rational points on higher genus curves, discussing questions ranging from the era of the ancient Greeks to a few posed by mathematicians of the 20th ...
    • Quasi-Equilibria and Click Times for a Variant of Muller's Ratchet 

      [OWP-2022-18] González Casanova, Adrian; Smadi, Charline; Wakolbinger, Anton (Mathematisches Forschungsinstitut Oberwolfach, 2022-11-30)
      Consider a population of $N$ individuals, each of them carrying a type in $\mathbb N_0$. The population evolves according to a Moran dynamics with selection and mutation, where an individual of type $k$ has the same selective ...
    • Route planning for bacteria 

      [SNAP-2022-012-EN] Hellmuth, Kathrin; Klingenberg, Christian (Mathematisches Forschungsinstitut Oberwolfach, 2022-12-08)
      Bacteria have been fascinating biologists since their discovery in the late 17th century. By analysing their movements, mathematical models have been developed as a tool to understand their behaviour. However, adapting ...
    • Closed geodesics on surfaces 

      [SNAP-2022-013-EN] Dozier, Benjamin (Mathematisches Forschungsinstitut Oberwolfach, 2022-12-08)
      We consider surfaces of three types: the sphere, the torus, and many-holed tori. These surfaces naturally admit geometries of positive, zero, and negative curvature, respectively. It is interesting to study straight line ...
    • Characterizations of intrinsic volumes on convex bodies and convex functions 

      [SNAP-2022-011-EN] Mussnig, Fabian (Mathematisches Forschungsinstitut Oberwolfach, 2022-12-08)
      If we want to express the size of a two-dimensional shape with a number, then we usually think about its area or circumference. But what makes these quantities so special? We give an answer to this question in terms of ...
    • Hutchinson's Intervals and Entire Functions from the Laguerre-Pólya Class 

      [OWP-2022-19] Nguyen, Thu Hien; Vishnyakova, Anna (Mathematisches Forschungsinstitut Oberwolfach, 2022-12-12)
      We find the intervals $[\alpha, \beta (\alpha)]$ such that if a univariate real polynomial or entire function $f(z) = a_0 + a_1 z + a_2 z^2 + \cdots $ with positive coefficients satisfy the conditions $ \frac{a_{k-1}^2}{ ...