Now showing items 1-20 of 28

• #### Right Simple Singularities in Positive Characteristic ﻿

[OWP-2013-28] (Mathematisches Forschungsinstitut Oberwolfach, 2013)
We classify isolated singularities $f \in K[[x_1,...,x_n]]$, which are simple, i.e. have no moduli, w.r.t. right equivalence, where $K$ is an algebraically closed field of characteristic $p>0$. For $K=\mathbb{R}$ or ...
• #### On the autonomous metric on groups of Hamiltonian diffeomorphisms of closed hyperbolic surfaces ﻿

[OWP-2013-18] (Mathematisches Forschungsinstitut Oberwolfach, 2013-07-23)
Let $\Sigma_g$ be a closed hyperbolic surface of genus $g$ and let Ham($\Sigma_ g$) be the group of Hamiltonian diffeomorphisms of $\Sigma_g$. The most natural word metric on this group is the autonomous metric. It has ...
• #### Supertropical Quadratic Forms I ﻿

[OWP-2013-27] (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 ...
• #### Obtaining Error-Minimizing Estimates and Universal Entry-Wise Error Bounds for Low-Rank Matrix Completion ﻿

[OWP-2013-12] (Mathematisches Forschungsinstitut Oberwolfach, 2013-06-10)
We propose a general framework for reconstructing and denoising single entries of incomplete and noisy entries. We describe: effective algorithms for deciding if and entry can be reconstructed and, if so, for reconstructing ...
• #### On Concentrators and Related Approximation Constants ﻿

[OWP-2013-14] (Mathematisches Forschungsinstitut Oberwolfach, 2013-06-10)
Pippenger ([Pip77]) showed the existence of (6m, 4m, 3m, 6)-concentrator for each positive integer m using a probabilistic method. We generalize his approach and prove existence of (6m, 4m, 3m, 5.05)-concentrator (which ...
• #### Mesh Ratios for Best-Packing and Limits of Minimal Energy Configurations ﻿

[OWP-2013-13] (Mathematisches Forschungsinstitut Oberwolfach, 2013-06-10)
For $N$-point best-packing configurations $\omega_N$ on a compact metric space $(A, \rho)$, we obtain estimates for the mesh-separation ratio $\gamma(\rho_N , A)$, which is the quotient of the covering radius of $\omega_N$ ...
• #### The algebraic combinatorial approach for low-rank matrix completion ﻿

[OWP-2013-05] (Mathematisches Forschungsinstitut Oberwolfach, 2013-03-14)
We propose an algebraic combinatorial framework for the problem of completing partially observed low-rank matrices. We show that the intrinsic properties of the problem, including which entries can be reconstructed, and ...
• #### Even-homogeneous supermanifolds on the complex projective line ﻿

[OWP-2013-02] (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 ...
• #### Enhanced Spatial Skin-Effect for Free Vibrations of a Thick Cascade Junction with "Super Heavy" Concentrated Masses ﻿

[OWP-2013-26] (Mathematisches Forschungsinstitut Oberwolfach, 2013-12-13)
The asymptotic behavior (as $\varepsilon \to 0$) of eigenvalues and eigenfunctions of a boundary-value problem for the Laplace operator in a thick cascade junction with concentrated masses is studied. This cascade junction ...
• #### A Relation Between N-Qubit and 2N-1-Qubit Pauli Groups via Binary LGr(N,2N) ﻿

[OWP-2013-25] (Mathematisches Forschungsinstitut Oberwolfach, 2013-12-09)