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Related papers: Memory Complexity of Quantum Processes

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"Quantum mechanics must be regarded as open systems. On one hand, this is due to the fact that, like in classical physics, any realistic system is subjected to a coupling to an uncontrollable environment which influences it in a…

Quantum Physics · Physics 2007-05-23 S. Nicolosi

The dynamics of open quantum system are often modeled by non-Markovian processes that account for memory effects arising from interactions with the environment. It is well-known that the memory provided by the environment can be classical…

Quantum Physics · Physics 2025-10-22 Charlotte Bäcker , Konstantin Beyer , Walter T. Strunz

The main goal of this paper is to give a rigorous mathematical description of systems for processing quantum information. To do it authors consider abstract state machines as models of classical computational systems. This class of machines…

Computational Complexity · Computer Science 2012-06-12 Mizal Alobaidi , Andriy Batyiv , Grygoriy Zholtkevych

Quantum systems have an exponentially large degree of freedom in the number of particles and hence provide a rich dynamics that could not be simulated on conventional computers. Quantum reservoir computing is an approach to use such a…

Quantum Physics · Physics 2020-11-11 Keisuke Fujii , Kohei Nakajima

We revise fundamental concepts in the dynamics of open quantum systems in the light of modern developments in the field. Our aim is to present a unified approach to the quantum evolution of open systems that incorporates the concepts and…

Quantum Physics · Physics 2013-07-29 Ángel Rivas , Susana F. Huelga

In classical mechanics the complexity of a dynamical system is characterized by the rate of local exponential instability which effaces the memory of initial conditions and leads to practical irreversibility. In striking contrast, quantum…

Quantum Physics · Physics 2009-02-24 Giuliano Benenti , Giulio Casati

Quantum memory effects are essential in understanding and controlling open quantum systems, yet distinguishing them from classical memory remains challenging. We introduce a convex geometric framework to analyze quantum memory propagating…

Quantum Physics · Physics 2025-04-14 Mei Yu , Ties-A. Ohst , Hai-Chau Nguyen , Stefan Nimmrichter

The model of open quantum systems is adopted to describe the non-local dynamical behaviour of qubits processed by entangling gates. The analysis gets to the conclusion that a distinction between evaluation steps and task-oriented computing…

Quantum Physics · Physics 2015-12-24 Stefano Bonzio , Paola Verrucchi

Non-Markovian quantum processes exhibit different memory effects when measured in different ways; an unambiguous characterization of memory length requires accounting for the sequence of instruments applied to probe the system dynamics.…

Quantum Physics · Physics 2019-04-11 Philip Taranto , Simon Milz , Felix A. Pollock , Kavan Modi

Characterisation protocols have so far played a central role in the development of noisy intermediate-scale quantum (NISQ) computers capable of impressive quantum feats. This trajectory is expected to continue in building the next…

Complex processes often arise from sequences of simpler interactions involving a few particles at a time. These interactions, however, may not be directly accessible to experiments. Here we develop the first efficient method for unravelling…

Quantum Physics · Physics 2022-06-24 Ge Bai , Ya-Dong Wu , Yan Zhu , Masahito Hayashi , Giulio Chiribella

Understanding temporal processes and their correlations in time is of paramount importance for the development of near-term technologies that operate under realistic conditions. Capturing the complete multi-time statistics defining a…

Quantum Physics · Physics 2020-04-28 Philip Taranto

Quantum thermodynamics studies how quantum systems and operations may be exploited as sources of work to perform useful thermodynamic tasks. In real-world conditions, the evolution of open quantum systems typically displays memory effects,…

Quantum Physics · Physics 2025-05-30 Guilherme Zambon , Gerardo Adesso

Quantum reservoir computing (QRC) harnesses driven quantum dynamics for time-series processing, yet the mechanisms behind the differing performance levels across its many implementations remain unclear. We show that apparently unrelated…

Quantum Physics · Physics 2026-03-24 Saud Čindrak , Lara Giebeler , Niclas Götting , Christopher Gies , Kathy Lüdge

A precise understanding of the influence of a quantum system's environment on its dynamics, which is at the heart of the theory of open quantum systems, is crucial for further progress in the development of controllable large-scale quantum…

Quantum Physics · Physics 2022-10-10 I. A. Luchnikov , E. O. Kiktenko , M. A. Gavreev , H. Ouerdane , S. N. Filippov , A. K. Fedorov

The quantum master equation (QME), used to describe the Markov process of interaction between atoms and field, has a number of significant drawbacks. It is extremely memory intensive, and also inapplicable to the case of long-term memory in…

Quantum Physics · Physics 2024-10-29 Yuri Ozhigov , You Jiangchuan

Algorithmic approach is based on the assumption that any quantum evolution of many particle system can be simulated on a classical computer with the polynomial time and memory cost. Algorithms play the central role here but not the…

Quantum Physics · Physics 2007-05-23 Yuri Ozhigov

Understanding whether the features of open quantum dynamics are genuinely quantum remains a central challenge in quantum dynamics. Even though the non-Markovian behavior of quantum dynamics has been widely investigated across different…

Quantum Physics · Physics 2026-04-09 Rajeev Gangwar , Ujjwal Sen

We present a method to detect quantum memory in a non-Markovian process. We call a process Markovian when the environment does not provide a memory that retains correlations across different system-environment interactions. We define two…

Quantum Physics · Physics 2021-04-28 Christina Giarmatzi , Fabio Costa

Quantum memory effects can be qualitatively understood as a consequence of an environment-to-system backflow of information. Here, we analyze and compare how this concept is interpreted and implemented in different approaches to quantum…

Quantum Physics · Physics 2022-05-09 Adrián A. Budini