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Related papers: Quantum Operations on Conformal Nets

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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

The symmetries of a finite graph are described by its automorphism group; in the setting of Woronowicz's quantum groups, a notion of a quantum automorphism group has been defined by Banica capturing the quantum symmetries of the graph. In…

Quantum Algebra · Mathematics 2019-07-01 Christian Eder , Viktor Levandovskyy , Julien Schanz , Simon Schmidt , Andreas Steenpass , Moritz Weber

Quantum general relativity may be considered as generally covariant QFT on differentiable manifolds, without any a priori metric structure. The kinematically covariance group acts by general diffeomorphisms on the manifold and by…

General Relativity and Quantum Cosmology · Physics 2007-05-23 M. Rainer

In our model a fixed Hamiltonian acts on the joint Hilbert space of a quantum system and its controller. We show under which conditions measurements, state preparations, and unitary implementations on the system can be performed by quantum…

Quantum Physics · Physics 2009-11-07 Dominik Janzing , Frederik Armknecht , Robert Zeier , Thomas Beth

In this work, we study a sub-collection of unital completely positive maps from a unital $C^\ast$-algebra $\mathcal{A}$ to $\mathcal{B}(\mathcal{H})$, the algebra of bounded linear operators on a Hilbert space $\mathcal{H}$ in the setting…

Operator Algebras · Mathematics 2026-01-23 Chaitanya J. Kulkarni

We give a general scheme for constructing faithful actions of genuine (noncommutative as $C^*$ algebra) compact quantum groups on classical topological spaces. Using this, we show that: (i) a compact connected classical space can have a…

Quantum Algebra · Mathematics 2009-10-06 Jyotishman Bhowmick , Debashish Goswami , Subrata Shyam Roy

We construct a sheaf-theoretic representation of quantum observables algebras over a base category equipped with a Grothendieck topology, consisting of epimorphic families of commutative observables algebras, playing the role of local…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Elias Zafiris

We analyse possibility to extend a quantum operation (sub-unital normal CP linear map on the algebra $B(H)$ of bounded operators on a separable Hilbert space $H$) to the space of all operators on $H$ relatively bounded w.r.t. a given…

Mathematical Physics · Physics 2020-11-16 M. E. Shirokov

We develop the theory of quantum (a.k.a. noncommutative) relations and quantum (a.k.a. noncommutative) graphs in the finite-dimensional covariant setting, where all systems (finite-dimensional $C^*$-algebras) carry an action of a compact…

Operator Algebras · Mathematics 2026-03-19 Dominic Verdon

Errors in the control of quantum systems may be classified as unitary, decoherent and incoherent. Unitary errors are systematic, and result in a density matrix that differs from the desired one by a unitary operation. Decoherent errors…

We provide several applications of a previously introduced isomorphism between physical operations acting on two systems and entangled states [1]. We show: (i) how to implement (weakly) non-local two qubit unitary operations with a small…

Quantum Physics · Physics 2009-11-06 W. Dür , J. I. Cirac

Let $d > 1$, and let $(X,\alpha)$ and $(Y,\beta)$ be two zero-entropy ${\mathbb{Z}}^d$-actions on compact abelian groups by $d$ commuting automorphisms. We show that if all lower rank subactions of $\alpha$ and $\beta$ have completely…

Dynamical Systems · Mathematics 2007-05-23 Siddhartha Bhattacharya

Let ${\mathcal B}(H)$ denote the Banach algebra of all bounded linear operators on a complex Hilbert space $H$ with $\dim H\geq 3$, and let $\mathcal A$ and $\mathcal B$ be subsets of ${\mathcal B}(H)$ which contain all rank one operators.…

Functional Analysis · Mathematics 2017-05-01 Jianlian Cui , Chi-Kwong Li , Nung-Sing Sze

Let $X$ be an Archimedean vector lattice. We investigate subalgebras of $\mathscr{L}(X)$ consisting of regular operators that contain all rank-one operators of the form $a \otimes \varphi_b$, where $a$ and $b$ are atoms of $X$ and…

Functional Analysis · Mathematics 2026-01-30 Gregor Cigler , Marko Kandić

There are several important abstract operator systems with the convex cone of positive semidefinite matrices at the first level. Well-known are the operator systems of separable matrices, of positive semidefinite matrices, and of block…

Operator Algebras · Mathematics 2021-09-30 Martin Berger , Tim Netzer

Let $M$ be a smooth manifold equipped with a conformal structure, $E[w]$ the space of densities with the the conformal weight $w$ and $D_{w,w+\de}$ the space of differential operators from $E[w]$ to $E[w+\delta]$. Conformal quantization $Q$…

Differential Geometry · Mathematics 2009-03-30 Josef Silhan

A topological group $G$ is called extremely amenable if every continuous action of $G$ on a compact space has a fixed point. This concept is linked with geometry of high dimensions (concentration of measure). We show that a von Neumann…

Operator Algebras · Mathematics 2007-09-03 Thierry Giordano , Vladimir Pestov

We explore the nonperturbative renormalization group flow of Quantum Einstein Gravity (QEG) on an infinite dimensional theory space. We consider "conformally reduced" gravity where only fluctuations of the conformal factor are quantized and…

High Energy Physics - Theory · Physics 2009-09-02 Martin Reuter , Holger Weyer

We formulate Nielsen's geometric approach to complexity in the context of two dimensional conformal field theories, where series of conformal transformations are interpreted as unitary circuits. We show that the complexity functional can be…

High Energy Physics - Theory · Physics 2019-06-19 Pawel Caputa , Javier M. Magan

We show the natural relation between the Wigner Hamiltonian and the conformal Hamiltonian. It is presented a model in (super)conformal quantum mechanics with (super)conformal symmetry in the Wigner-Heisenberg algebra picture $ [x,p_{x}]=…

High Energy Physics - Theory · Physics 2014-11-18 H. L. Carrion , R. de Lima Rodrigues