English
Related papers

Related papers: Complete positivity and contextuality of quantum d…

200 papers

A new, realist interpretation of the quantum measurement processes is given. In this scenario a quantum measurement is a non-equilibrium phase transition in a ``resonant cavity'' formed by the entire physical universe including all its…

Quantum Physics · Physics 2009-11-13 Xiaolei Zhang

The paper studies differentially positive systems, that is, systems whose linearization along an arbitrary trajectory is positive. We illustrate the use of differential positivity on compact forward invariant sets for the characterization…

Systems and Control · Computer Science 2015-08-19 Fulvio Forni

We investigate the relationship between strict positivity of the Kossakowski matrix, irreducibility and positivity improvement properties of Markovian Quantum Dynamics. We show that for a Gaussian quantum dynamical semigroup strict…

Quantum Physics · Physics 2025-04-01 Julián Agredo , Franco Fagnola , Damiano Poletti

We consider a physical system in which the description of states and measurements follow the usual quantum mechanical rules. We also assume that the dynamics is linear, but may not be fully quantum (i.e unitary). We show that in such a…

Quantum Physics · Physics 2009-10-31 Aditi Sen De , Ujjwal Sen

A proof using the theory of completely positive maps is given to the fact that if $A \in M_2$, or $A \in M_3$ has a reducing eigenvalue, then every bounded linear operator $B$ with $W(B) \subseteq W(A)$ has a dilation of the form $I \otimes…

Functional Analysis · Mathematics 2019-02-07 Chi-Kwong Li , Yiu-Tung Poon

We argue that notions in quantum theory should have universal properties in the sense of category theory. We consider the completely positive trace preserving (CPTP) maps, the basic notion of quantum channel. Physically, quantum channels…

Quantum Physics · Physics 2019-01-30 Mathieu Huot , Sam Staton

The prevailing description for dissipative quantum dynamics is given by the Lindblad form of a Markovian master equation, used under the assumption that memory effects are negligible. However, in certain physical situations, the master…

Quantum Physics · Physics 2009-11-10 Sonja Daffer , Krzysztof Wodkiewicz , James D. Cresser , John K. McIver

The relation between completely positive maps and compound states is investigated in terms of the notion of quantum conditional probability.

Quantum Physics · Physics 2007-05-23 M. Asorey , A. Kossakowski , G. Marmo , E. C. G. Sudarshan

This article focuses on the general theory of open quantum systems in the Gaussian regime and explores a number of diverse ramifications and consequences of the theory. We shall first introduce the Gaussian framework in its full generality,…

Quantum Physics · Physics 2017-01-19 Marco G. Genoni , Ludovico Lami , Alessio Serafini

We describe a scheme of quantum computation with magic states on qubits for which contextuality is a necessary resource possessed by the magic states. More generally, we establish contextuality as a necessary resource for all schemes of…

Quantum Physics · Physics 2017-06-27 Robert Raussendorf , Dan E. Browne , Nicolas Delfosse , Cihan Okay , Juan Bermejo-Vega

We report a method that exploits a connection between quantum contextuality and graph theory to reveal any form of quantum contextuality in high-precision experiments. We use this technique to identify a graph which corresponds to an…

Any evolution described by a completely positive trace-preserving linear map can be imagined as arising from the interaction of the evolving system with an initially uncorrelated ancilla. The interaction is given by a joint unitary…

Quantum Physics · Physics 2013-06-21 Zhang Jiang , Marco Piani , Carlton M. Caves

We obtain exact analytic expressions for a class of functions expressed as integrals over the Haar measure of the unitary group in d dimensions. Based on these general mathematical results, we investigate generic dynamical properties of…

Quantum Physics · Physics 2013-04-30 Manuel Gessner , Heinz-Peter Breuer

We study the dynamics of a quantum system in which an intermediate property $m$ is measured in between initial and final measurements of two different non-commuting properties $a$ and $b$. Since this intermediate measurement must involve an…

Quantum Physics · Physics 2020-10-06 Hollis Williams

We propose and evaluate experimentally an approach to quantum process tomography that completely removes the scaling problem plaguing the standard approach. The key to this simplification is the incorporation of prior knowledge of the class…

Quantum Physics · Physics 2015-05-14 M. P. A. Branderhorst , J. Nunn , I. A. Walmsley , R. L. Kosut

We introduce a constructive procedure that maps all spatial correlations of a broad class of states into temporal correlations between general quantum measurements. This allows us to present temporal phenomena analogous to genuinely…

Quantum Physics · Physics 2014-06-25 Marcin Markiewicz , Anna Przysiezna , Stephen Brierley , Tomasz Paterek

We study quantum causal inference in a set-up proposed by Ried et al. [Nat. Phys. 11, 414 (2015)] in which a common-cause scenario can be mixed with a cause-effect scenario, and for which it was found that quantum mechanics can bring an…

Quantum Physics · Physics 2019-12-24 Jonas Kübler , Daniel Braun

The theory of quantum dynamical semigroups within the mathematically rigorous framework of completely positive dynamical maps is reviewed. First, the axiomatic approach which deals with phenomenological constructions and general…

Quantum Physics · Physics 2007-05-23 Robert Alicki

We study the problem of whether all bipartite quantum states having a prescribed spectrum remain positive under the reduction map applied to one subsystem. We provide necessary and sufficient conditions, in the form of a family of linear…

Quantum Physics · Physics 2015-03-16 Maria Anastasia Jivulescu , Nicolae Lupa , Ion Nechita , David Reeb

We consider scenarios where the dynamics of a quantum system are partially determined by prior local measurements of some interacting environmental degrees of freedom. The resulting effective system dynamics are described by a disordered…

Quantum Physics · Physics 2024-05-06 Šárka Blahnik , Sarah Shandera