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Related papers: $k$-decomposability of positive maps

200 papers

We study k-positive maps on operators. Proofs are given to different positivity criteria. Special attention is on positive maps arising in the study of quantum information science. Results of other researchers are extended and improved. New…

Quantum Physics · Physics 2013-03-14 Jinchuan Hou , Chi-Kwong Li , Yiu-Tung Poon , Xiaofei Qi , Nung-Sing Sze

We give new lower bounds for the (higher) topological complexity of a space, in terms of the Lusternik-Schnirelmann category of a certain auxiliary space. We also give new lower bounds for the rational topological complexity of a space, and…

Algebraic Topology · Mathematics 2016-01-20 Mark Grant , Gregory Lupton , John Oprea

In this paper, we introduce two new forms of the dual Hartwig-Spindelb{\"o}ck decomposition and employ them to derive explicit representations for several classes of dual generalized inverses. Building on these representations, we further…

Rings and Algebras · Mathematics 2026-02-10 Tan Mei , Kezheng Zuo , Hui Yan

It is proved that the assembly map in algebraic K- and L-theory with respect to the family of finite subgroups is injective for groups $\Gamma$ with finite quotient finite decomposition complexity (a strengthening of finite decomposition…

K-Theory and Homology · Mathematics 2015-07-28 Daniel Kasprowski

We construct the deformation functor associated with a pair of morphisms of differential graded Lie algebras, and use it to study infinitesimal deformations of holomorphic maps of compact complex manifolds. In particular, using L-infinity…

Algebraic Geometry · Mathematics 2008-04-03 Donatella Iacono

The decomposition into interaction subspaces is an important result for graphical models and plays a central role for results on the linearized marginal problem; similarly the Chaos decomposition plays an important role in statistical…

Category Theory · Mathematics 2021-07-15 Grégoire Sergeant-Perthuis

The structure of the set of positivity-preserving maps between matrix algebras is notoriously difficult to describe. The notable exceptions are the results by St{\o}rmer and Woronowicz from 1960s and 1970s settling the low dimensional…

Functional Analysis · Mathematics 2015-12-11 Guillaume Aubrun , Stanisław J. Szarek

The problem of decomposing a given covariance matrix as the sum of a positive semi-definite matrix of given rank and a positive semi-definite diagonal matrix, is considered. We present a projection-type algorithm to address this problem.…

Optimization and Control · Mathematics 2018-06-13 Valentina Ciccone , Augusto Ferrante , Mattia Zorzi

Following an idea of Choi, we obtain a decomposition theorem for k-positive linear maps from Mm to Mn, where 2<=k<min{m,n}. As a consequence, we give an affirmative answer to Kye's conjecture (also solved independently by Choi) that every…

Mathematical Physics · Physics 2016-03-14 Yu Yang , Denny H. Leung , Waishing Tang

A space has $\sigma$-compact tightness if the closures of $\sigma$-compact subsets determines the topology. We consider a dense set variant that we call densely k-separable. We consider the question of whether every densely k-separable…

General Topology · Mathematics 2018-10-12 Alan Dow , Istvan Juhasz

We realize the infinitesimal Abel-Jacobi map as a morphism of formal deformation theories, realized as a morphism in the homotopy category of differential graded Lie algebras. The whole construction is carried out in a general setting, of…

Quantum Algebra · Mathematics 2018-06-20 Domenico Fiorenza , Marco Manetti

The task of reconstructing a matrix given a sample of observedentries is known as the matrix completion problem. It arises ina wide range of problems, including recommender systems, collaborativefiltering, dimensionality reduction, image…

Statistics Theory · Mathematics 2014-12-20 Jean Lafond , Olga Klopp , Eric Moulines , Jospeh Salmon

By using K-theory, we construct a map from the tangent space to the Hilbert scheme at a point Y to the local cohomology group. And we use this map to answer affirmatively(after slight modification) a question by Mark Green and Phillip…

Algebraic Geometry · Mathematics 2018-12-26 Sen Yang

It is a well-known result due to E. St{\o}rmer that every positive qubit map is decomposable into a sum of a completely positive map and a completely copositive map. Here, we generalize this result to tensor squares of qubit maps.…

Quantum Physics · Physics 2021-09-15 Alexander Müller-Hermes

In this thesis we study the relationship between the existence of canonical metrics on a complex manifold and stability in the sense of geometric invariant theory. We introduce a modification of K-stability of a polarised variety which we…

Differential Geometry · Mathematics 2007-05-23 Gábor Székelyhidi

The purpose of this paper is to generalise Sullivan's rational homotopy theory to non-nilpotent spaces, providing an alternative approach to defining Toen's schematic homotopy types over any field k of characteristic zero. New features…

Algebraic Topology · Mathematics 2009-02-04 J. P. Pridham

In this article we study fine regularity properties for mappings of finite distortion. Our main theorems yield strongly localized regularity results in the borderline case in the class of maps of exponentially integrable distortion.…

Complex Variables · Mathematics 2021-09-28 Olli Hirviniemi , István Prause , Eero Saksman

The decomposition problem of the enveloping algebra of a simple Lie algebra is reconsidered combining both the analytical and the algebraic approach, showing its relation with the internal labelling problem with respect to a nilpotent…

Mathematical Physics · Physics 2024-03-05 Rutwig Campoamor-Stursberg , Ian Marquette

We give a description of a weakly continuous rank preserving map on a reflexive algebra on complex Hilbert space with commutative completely distributive subspace lattice. We show that the implementation of a rank preserving map can be…

Operator Algebras · Mathematics 2007-05-23 Jaedeok Kim , Robert L. Moore

We take matrix decompositions that are usually applied to matrices over the real numbers or complex numbers, and extend them to matrices over an algebra called the double numbers. In doing so, we unify some matrix decompositions: For…

Rings and Algebras · Mathematics 2021-12-07 Ran Gutin