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Related papers: Exposed positive maps in M_4(C)

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In the setting of step two Carnot groups, we show a "cone property" for horizontally convex sets. Namely we prove that, given a horizontally convex set $C$, a pair of points $P\in \partial C$ and $Q\in $ int $C$, both belonging to a…

Metric Geometry · Mathematics 2019-02-26 Daniele Morbidelli

In this note we prove that a four-dimensional compact oriented half-confor\-mally flat Riemannian manifold $M^4$ is topologically $\mathbb{S}^{4}$ or $\mathbb{C}\mathbb{P}^{2},$ provided that the sectional curvatures all lie in the interval…

Differential Geometry · Mathematics 2020-03-17 R. Diógenes , E. Ribeiro , E. Rufino

A family of random matrices is said to converge strongly to a limiting family of operators if the operator norm of every noncommutative polynomial of the matrices converges to that of the limiting operators. Recent developments surrounding…

Probability · Mathematics 2025-10-15 Ramon van Handel

Some fixed point results are given for a class of Meir-Keeler contractive maps acting on metric spaces endowed with locally transitive relations. Technical connections with the related statements due to Berzig et al [Abstr. Appl. Anal.,…

General Topology · Mathematics 2013-12-06 Mihai Turinici

Convex or concave sequences of $n$ positive terms, viewed as vectors in $n$-space, constitute convex cones with $2n-2$ and $n$ extreme rays, respectively. Explicit description is given of vectors spanning these extreme rays, as well as of…

Combinatorics · Mathematics 2013-12-05 Stephan Foldes , Laszlo Major

We consider the action of a real reductive group G on a Kaehler manifold Z which is the restriction of a holomorphic action of the complexified group G^C. We assume that the induced action of a compatible maximal compact subgroup U of G^C…

Complex Variables · Mathematics 2007-10-08 Peter Heinzner , Patrick Schuetzdeller

This note defines a family of Laurent polynomials (indexed in the rational projective line) which generalize the Markoff numbers and relate to the character variety of the one-cusped torus. We describe which monomials appear in each…

Number Theory · Mathematics 2007-05-23 Francois Gueritaud

We construct a family of monotone and convex $C^1$ integro cubic splines under a strictly convex position of the dataset. Then, we find an optimal spline by considering its approximation properties. Finally, we give some examples to…

Numerical Analysis · Mathematics 2020-03-13 Tugal Zhanlav , Renchin-Ochir Mijiddorj

In this paper we characterize smooth complex projective varieties that admit a quadric bundle structure on some dense open subset in terms of the geometry of certain families of rational curves.

Algebraic Geometry · Mathematics 2008-11-07 Carolina Araujo

Extending Wigner's theorem we give a characterization of positive maps of $B(H)$ into itself which map the set of rank k projections onto itself.

Operator Algebras · Mathematics 2016-04-21 Erling Størmer

The versatility of exponential families, along with their attendant convexity properties, make them a popular and effective statistical model. A central issue is learning these models in high-dimensions, such as when there is some sparsity…

Machine Learning · Computer Science 2015-05-19 Sham M. Kakade , Ohad Shamir , Karthik Sridharan , Ambuj Tewari

We show that nuclear C*-algebras have a refined version of the completely positive approximation property, in which the maps that approximately factorize through finite dimensional algebras are convex combinations of order zero maps. We use…

Operator Algebras · Mathematics 2012-04-27 Ilan Hirshberg , Eberhard Kirchberg , Stuart White

Using the notion of the normalized duality map it is characterized the class of the uniformly convex uniformly smooth Banach spaces in which each convex cone has a convex polar.

Functional Analysis · Mathematics 2025-07-31 A. B. Németh

The current work is motivated by the papers $[B_3]$, $[B_6]$, $[Be]$, $[Be-Tu]$. In particular, using Theorem 3.7 of $[B_3]$ and methods developed in this paper, the spectral and strong homology groups of continuous maps were defined and…

Algebraic Topology · Mathematics 2017-05-09 Anzor Beridze , Vladimer Baladze

We characterize a set of positive maps in matrix algebra of 4x4 complex matrices. Equivalently, we provide a subset of entanglement witnesses parameterized by the rotation group SO(3). Interestingly, these maps/witnesses define two…

Quantum Physics · Physics 2013-02-06 Dariusz Chruściński , Filip A. Wudarski

We show that the strengthened version of the completely positive approximation property of Brown, Carri\'on, and White---where the downward maps are asymptotically order zero and the upward maps are convex combinations of order zero…

Operator Algebras · Mathematics 2019-11-05 José R. Carrión , Christopher Schafhauser

The purpose of this paper is to show that all maximally planar subgraphs of graphs in the Petersen Family have associated conflict graphs unbalanced. All but three strong conflict graphs arising from Petersen Family Graphs are unbalanced,…

Combinatorics · Mathematics 2023-02-28 Joel Foisy , Justin Raimondi

Integral representations for continuous polynomial local functionals on convex functions are established in terms of a finite family of polynomials. This result is obtained by approximation from a classification of the dense subspace of…

Functional Analysis · Mathematics 2026-04-28 Jonas Knoerr

We prove that all locally exposable points in a Stein compact in a complex space can be exposed along a given curve to a given real hypersurface. Moreover, the exposing map for a boundary point can be sufficiently close to the identity map…

Complex Variables · Mathematics 2016-07-12 Fusheng Deng , John Erik Fornaess , Erlend Fornaess Wold

We present a partial characterization of matrices in $M_n(\cA)^+$ satisfying the St{\o}rmer condition.

Mathematical Physics · Physics 2008-06-20 W. A. Majewski