Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Log inSign up
Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Blog
Job Board
Q3AS

© 2026 Aqora Quantum S.A.S.

TermsPrivacyLegal Notice

arXiv:1603.03534

All 2-positive linear maps from M3 to M3 are decomposable

Yang Yu, Denny H. Leung, Wai-Shing Tang

Published Mar 11, 2016• 2 citations
arXivHTMLPDF

Abstract

Following an idea of Choi, we obtain a decomposition theorem for k-positive linear maps from Mm to Mn, where 2<=k
DOI
10.48550/arxiv.1603.03534

Related papers

All 2-positive linear maps from M3(C) to M3(C) are decomposable

Yang Yu, Denny H. Leung, Wai-Shing Tang

Linear Algebra and its Applications•Apr 21, 2016•22 citations

Generalizing Choi map in $M_3$ beyond circulant scenario

Anindita Bera, Scala, Giovanni, Gniewomir Sarbicki +1 more

We present a generalization of the family of linear positive maps in $M_3$ proposed thirty years ago by Cho et al. (Linear Algebra Appl. ${\bf 171}$, 213 (1992)) as a generalization of the seminal Choi non-decomposable map. The necessary and sufficient conditions for decomposability are provided.

arXiv:2212.03807•Dec 7, 2022•0 citations

Decomposable of positive map from M3(C) to M2(M2(C))

Winda C. Akatch, Okelo B. Nyaare, Priscah Mogotu Omoke

In most literature, the decomposition of positive maps from M3 to M2 are discussed where the matrix elements are complex numbers. In this paper we construct a positive maps φ(µ,c1,c2) from M3(C) to M2(M2(C)). The Choi matrices for complete positivity and complete copositivity ares visualized as tensor matrix M3 ⊗M2 with M2(C) as the entry elements. The construction allow us describe decomposability on positive semidefinite matrices.

Journal of Mathematical Analysis and Modeling•Dec 29, 2023•0 citations

On decomposability of positive maps between $M_2$ and $M_n$

W. A. Majewski, Marcin Marciniak

A map $ϕ:M_m(\bC)\to M_n(\bC)$ is decomposable if it is of the form $ϕ=ϕ_1+ϕ_2$ where $ϕ_1$ is a CP map while $ϕ_2$ is a co-CP map. A partial characterization of decomposability for maps $ϕ: M_2(\bC) \to M_3(\bC)$ is given.

arXiv:math/0510138•Oct 7, 2005•2 citations

Indecomposable Positive Maps in Matrix Algebras

Kôtarô Tanahashi, Jun Tomiyama

Abstract We prove that Choi's map in M3 cannot be written as the sum of a 2-positive map and a 2-copositive map. We also provide other examples of positive maps in Mn which cannot be written as the sum of an n-positive map and a 2-copositive map.

Canadian Mathematical Bulletin•Sep 1, 1988•77 citations

A Class of Extremal Positive Maps in $3 \times 3$ Matrix Algebras

Hiroyuki Osaka

We shall provide a large class of extremal positive maps in M_3(\mathbf C) which are neither 2-positive nor 2-copositive and study the algebraic structure of the set of all positive linear maps in M_3(\mathbf C) .

Publications of the Research Institute for Mathematical Sciences•Oct 31, 1992•37 citations
Generalizing Choi map in M3M_3M3​ beyond circulant scenario
We present a generalization of the family of linear positive maps in M3M_3M3​ proposed thirty years ago by Cho et al. (Linear Algebra Appl. 171{\bf 171}171, 213 (1992)) as a generalization of the seminal Choi non-decomposable map. The necessary and sufficient conditions for decomposability are provided.
On decomposability of positive maps between M2M_2M2​ and MnM_nMn​
A map $ϕ:M_m(\bC)\to M_n(\bC)$ is decomposable if it is of the form ϕ=ϕ1+ϕ2ϕ=ϕ_1+ϕ_2ϕ=ϕ1​+ϕ2​ where ϕ1ϕ_1ϕ1​ is a CP map while ϕ2ϕ_2ϕ2​ is a co-CP map. A partial characterization of decomposability for maps $ϕ: M_2(\bC) \to M_3(\bC)$ is given.
A Class of Extremal Positive Maps in 3×33 \times 33×3 Matrix Algebras