English
Related papers

Related papers: Complete positivity on the subsystems level

200 papers

We derive a purely algebraic framework for the identification of hierarchy equations of motion that induce completely positive dynamics and demonstrate the applicability of our approach with several examples. We find bounds on the violation…

Quantum Physics · Physics 2016-08-25 Björn Witt , Łukasz Rudnicki , Yoshitaka Tanimura , Florian Mintert

Semi-Markov processes represent a well known and widely used class of random processes in classical probability theory. Here, we develop an extension of this type of non-Markovian dynamics to the quantum regime. This extension is…

Quantum Physics · Physics 2009-04-30 Heinz-Peter Breuer , Bassano Vacchini

We study dynamical semigroups of positive, but not completely positive maps on finite-dimensional bipartite systems and analyze properties of their generators in relation to non-decomposability and bound-entanglement. An example of…

Quantum Physics · Physics 2015-06-26 F. Benatti , R. Floreanini , M. Piani

A new quantum mechanical notion -- Conditional Density Matrix -- is discussed and is applied to describe some physical processes. This notion is a natural generalization of von Neumann density matrix for such processes as divisions of…

Quantum Physics · Physics 2007-05-23 V. V. Belokurov , O. A. Khrustalev , V. A. Sadovnichy , O. D. Timofeevskaya

Using the known possibility to associate the completely positive maps with density matrices and recent results on expressing the density matrices with sets of classical probability distributions of dichotomic random variables we construct…

Quantum Physics · Physics 2019-04-09 Ashot Avanesov , Vladimir I. Man'ko

A system interacting with its environment will give rise to a quantum evolution. After tracing over the environment the net evolution of the system can be described by a linear Hermitian map. It has recently been shown that a necessary and…

Quantum Physics · Physics 2015-03-17 Yong-Cheng Ou , C. Allen Bishop , Mark S. Byrd

The mathematical possibility of coupling two quantum dynamic systems having two different Planck constants, respectively, is investigated. It turns out that such canonical dynamics are always irreversible. Semiclassical dynamics is obtained…

Quantum Physics · Physics 2007-05-23 Lajos Diosi

We describe a broad dynamical-algebraic framework for analyzing the quantum control properties of a set of naturally available interactions. General conditions under which universal control is achieved over a set of subspaces/subsystems are…

Quantum Physics · Physics 2009-11-10 P. Zanardi , S. Lloyd

Quantum dynamical maps provide suitable mathematical representation of quantum evolutions. It is the very notion of complete positivity which provides a proper mathematical representation of quantum evolution and gives rise to the powerful…

Quantum Physics · Physics 2022-09-30 Dariusz Chruściński

Completely positive trace preserving maps are widely used in quantum information theory. These are mostly studied using the master equation perspective. A central part in this theory is to study whether a given system of dynamical maps…

Functional Analysis · Mathematics 2026-02-06 Bihalan Bhattacharya , Uwe Franz , Saikat Patra , Ritabrata Sengupta

The dynamics of an open quantum system can be described by a quantum operation, a linear, complete positive map of operators. Here, I exhibit a compact expression for the time reversal of a quantum operation, which is closely analogous to…

Quantum Physics · Physics 2008-04-03 Gavin E. Crooks

We introduce a framework for the construction of completely positive maps for subsystems of indistinguishable fermionic particles. In this scenario, the initial global state is always correlated, and it is not possible to tell system and…

For a given set of input-output pairs of quantum states or observables, we ask the question whether there exists a physically implementable transformation that maps each of the inputs to the corresponding output. The physical maps on…

Mathematical Physics · Physics 2012-10-24 Teiko Heinosaari , Maria A. Jivulescu , David Reeb , Michael M. Wolf

In this work we examine quantum states which have non-negative amplitudes (in a fixed basis) and the channels which preserve them. These states include the ground states of stoquastic Hamiltonians and they are of interest since they avoid…

Quantum Physics · Physics 2022-09-08 Nathaniel Johnston , Jamie Sikora

The Kraus representation of quantum channels allows for a precise emulation of the complex dynamics that take place on quantum processors, whether for benchmarking algorithms, predicting the performance of error correction and mitigation,…

Quantum Physics · Physics 2026-03-13 Shahrukh Chishti , Francisco Andrés Cárdenas-López , Felix Motzoi

The vast majority of the literature dealing with quantum dynamics is concerned with linear evolution of the wave function or the density matrix. A complete dynamical description requires a full understanding of the evolution of measured…

We use the Koashi-Imoto decomposition of the degrees of freedom of joint system-environment initial states to investigate the reduced dynamics. We show that a subset of joint system-environment initial states guarantees completely positive…

Quantum Physics · Physics 2016-06-07 Xiao-Ming Lu

The purpose of physics is to describe nature from elementary particles all the way up to cosmological objects like cluster of galaxies and black holes. Although a unified description for all this spectrum of events is desirable, this would…

Quantum Physics · Physics 2017-09-20 Cristhiano Duarte , Gabriel Dias Carvalho , Nadja K. Bernardes , Fernando de Melo

We consider a quaternionic quantum formalism for the description of quantum states and quantum dynamics. We prove that generalized quantum measurements on physical systems in quaternionic quantum theory can be simulated by usual quantum…

Quantum Physics · Physics 2015-07-29 Matthew A. Graydon

Quantum conditions on the control of dynamics of a system coupled to an environment are obtained. Specifically, consider a system initially in a system subspace $H_{0}$ of dimensionality $M_{0}$, which evolves to populate system subspaces…

Quantum Physics · Physics 2009-11-13 Lian-Ao Wu , Arjun Bharioke , Paul Brumer