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Related papers: A note on fixed points of completely positive maps

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A recent result characterizes the fully order reversing operators acting on the class of lower semicontinuous proper convex functions in a real Banach space as certain linear deformations of the Legendre-Fenchel transform. Motivated by the…

Classical Analysis and ODEs · Mathematics 2019-04-09 Alfredo N. Iusem , Daniel Reem , Simeon Reich

We consider transformation maps on the space of states which are symmetries in the sense of Wigner. Due to the convex nature of the space of states, the set of these maps has a convex structure. We investigate the possibility of a complete…

Mathematical Physics · Physics 2011-11-22 Janusz Grabowski , Marek Kus , Giuseppe Marmo

For a disk $D$ in the plane $\mathbb R^2$ and a plane map $f$, we give several conditions on the restriction of $f$ to the boundary $\partial D$ of $D$ which imply the existence of a fixed point of $f$ in some specified domain in $D$. These…

Dynamical Systems · Mathematics 2024-02-27 Jiehua Mai , Enhui Shi , Kesong Yan , Fanping Zeng

In this paper we study fixed point properties for semitopological semigroup of nonexpansive mappings on a bounded closed convex subset of a Banach space. We also study a Schauder fixed point property for a semitopological semigroup of…

Functional Analysis · Mathematics 2012-07-20 A. T. -M. Lau , Yong Zhang

In this work, using a new geometrical approach we study to the existence of the fixed-point of mappings that independence of the smoothness, and also of their single-values or multi-values. This work proved the theorems that generalize in…

Analysis of PDEs · Mathematics 2022-03-22 Kamal N. Soltanov

We define the infinite dimensional simplex to be the closure of the convex hull of the standard basis vectors in R^infinity, and prove that this space has the 'fixed point property': any continuous function from the space into itself has a…

General Topology · Mathematics 2007-08-28 Douglas Rizzolo , Francis Edward Su

We show that a continuous map or a continuous flow on $\R^{n}$ with a certain recurrence relation must have a fixed point. Specifically, if there is a compact set W with the property that the forward orbit of every point in $\R^{n}$…

Dynamical Systems · Mathematics 2007-05-23 David Richeson , Jim Wiseman

We first prove that in a sigma-finite von Neumann factor M, a positive element $a$ with properly infinite range projection R_a is a linear combination of projections with positive coefficients if and only if the essential norm ||a||_e with…

Operator Algebras · Mathematics 2010-07-28 Herbert Halpern , Victor Kaftal , Ping Wong Ng , Shuang Zhang

In this paper, first some results of [5] are extended for subadditive separating maps between C(X;E) and C(Y;E), such that E is a unital Banach algebra. Then we give some conditions under which a strongly subadditive map has a unique fixed…

Functional Analysis · Mathematics 2015-06-02 Yousef Estaremi , Bahman Moeini

We explore positivity properties of the semigroup generated by the negative of the Dirichlet-to-Neumann operator with real potential $\lambda$, defined on a subset of the vertices of a quantum graph. We show that for rationally independent…

Spectral Theory · Mathematics 2025-02-25 Daniel Daners , Jochen Glück , James B. Kennedy

In this article we characterize the extreme points of the unit ball of a non-commutative (quantum) Lorentz space associated with a semi-finite von Neumann algebra. This enables us to show that surjective isometries between non-commutative…

Operator Algebras · Mathematics 2021-01-12 Pierre de Jager , Jurie Conradie

If $f:[a,b]\to \mathbb{R}$, with $a<b$, is continuous and such that $a$ and $b$ are mapped in opposite directions by $f$, then $f$ has a fixed point in $I$. Suppose that $f:\mathbb{C}\to\mathbb{C}$ is map and $X$ is a continuum. We extend…

General Topology · Mathematics 2016-01-25 Alexander Blokh , Lex Oversteegen

A well-known result from Brouwer states that any orientation preserving homeomorphism of the plane with no fixed points has an empty non-wandering set. In particular, an invariant compact set implies the existence of a fixed point. In this…

Dynamical Systems · Mathematics 2019-06-11 Alejo García

Let $X$ be a complex Banach space with $\dim X\geq3$ and $B(X)$ the algebra of all bounded linear operators on $X$. Suppose $\phi:B(X)\longrightarrow B(X)$ is a surjective map satisfying the following property: $Fix(AB)=Fix(\phi(A)\phi(B)),…

Functional Analysis · Mathematics 2013-08-19 Ali Taghavi , Roja Hosseinzadeh , Vahid Darvish

In the present article, we show the existence of a coupled fixed point for an order preserving mapping in a preordered left K-complete quasi-pseudometric space using a preorder induced by an appropriate function. We also define the concept…

General Mathematics · Mathematics 2014-11-14 Yaé Ulrich Gaba

In this paper, we prove that if $\mathcal{A}=\{E_i\}_{i=1}^{n}$ is a finite commutative quantum measurement, then the fixed points set of L\"{u}ders operation $L_{{\cal A}}$ is the commutant ${\cal A}'$ of ${\cal A}$, the result answers an…

Mathematical Physics · Physics 2016-09-30 Liu Weihua , Wu Junde

We present a fixed point theorem on topological cylinders in normed linear spaces for maps satisfying a property of stretching a space along paths. This result is a generalization of a similar theorem obtained by D. Papini and F. Zanolin.…

General Topology · Mathematics 2015-03-27 Guglielmo Feltrin

Any maximal monotone operator can be characterized by a convex function. The family of such convex functions is invariant under a transformation connected with the Fenchel-Legendre conjugation. We prove that there exist a convex…

Functional Analysis · Mathematics 2008-03-11 B. F. Svaiter

We show that each positive map from B(K) to B(H) with K and H finite dimensional Hilbert spaces is a scalar multiple of a map of the form $Tr - \psi$ with $\psi$ completely positive. This is used to give necessary and sufficient conditions…

Operator Algebras · Mathematics 2010-09-30 Erling Størmer

We say a completely positive contractive map between two C*-algebras has order zero, if it sends orthogonal elements to orthogonal elements. We prove a structure theorem for such maps. As a consequence, order zero maps are in one-to-one…

Operator Algebras · Mathematics 2009-03-20 Wilhelm Winter , Joachim Zacharias