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Related papers: Predictive complexity of quantum subsystems

200 papers

Characterizing complexity and criticality in quantum systems requires diagnostics that are both computationally tractable and physically insightful. We apply a measure of quantum state complexity for n-qubit systems, defined as the…

Quantum Physics · Physics 2026-02-10 Imre Varga

Entanglement is a quantum resource, in some ways analogous to randomness in classical computation. Inspired by recent work of Gheorghiu and Hoban, we define the notion of "pseudoentanglement'', a property exhibited by ensembles of…

Optimal universal entanglement processes are discussed which entangle two quantum systems in an optimal way for all possible initial states. It is demonstrated that the linear character of quantum theory which enforces the peaceful…

Quantum Physics · Physics 2007-05-23 G. Alber

We present a description of entanglement in composite quantum systems in terms of symplectic geometry. We provide a symplectic characterization of sets of equally entangled states as orbits of group actions in the space of states. In…

Mathematical Physics · Physics 2016-01-19 Adam Sawicki , Alan Huckleberry , Marek Kuś

By representing an event as the joint state of a detector-timer couple that interact with a system, we recover the familiar tensor product structure, used to describe spatially separated systems, in the context of timelike events.…

Quantum Physics · Physics 2022-03-03 Aditya Iyer , Eduardo O. Dias , Vlatko Vedral

Characterizing the quantum complexity of local random quantum circuits is a very deep problem with implications to the seemingly disparate fields of quantum information theory, quantum many-body physics and high energy physics. While our…

Quantum Physics · Physics 2021-03-03 Jason Iaconis

Analyzing the properties of entanglement in many-particle spin-1/2 systems is generally difficult because the system's Hilbert space grows exponentially with the number of constituent particles, $N$. Fortunately, it is still possible to…

Quantum Physics · Physics 2007-05-23 John K. Stockton , JM Geremia , Andrew C. Doherty , Hideo Mabuchi

We investigate how the dynamical production of quantum entanglement for weakly coupled mapping systems is influenced by the chaotic dynamics of the corresponding classical system. We derive a general perturbative formula for the…

Quantum Physics · Physics 2015-06-26 Hiroshi Fujisaki , Atushi Tanaka , Takayuki Miyadera

A model of discrete dynamics of entanglement of bipartite quantum state is considered. It involves a global unitary dynamics of the system and periodic actions of local bistochastic or decaying channel. For initially pure states the decay…

Quantum Physics · Physics 2009-11-06 Karol Zyczkowski , Pawel Horodecki , Michal Horodecki , Ryszard Horodecki

Quantum entanglement, crucial for understanding quantum many-body systems and quantum gravity, is commonly assessed through various measures such as von Neumann entropy, mutual information, and entanglement contour, each with its inherent…

Quantum Physics · Physics 2025-07-08 Liang-Hong Mo , Yao Zhou , Jia-Rui Sun , Peng Ye

Prediction of events is the challenge in many different disciplines, from meteorology to finance; the more this task is difficult, the more a system is {\it complex}. Nevertheless, even according to this restricted definition, a general…

chao-dyn · Physics 2007-05-23 Maurizio Serva

Entanglement is one of the pillars of quantum mechanics and quantum information processing, and as a result the quantumness of nonentangled states has typically been overlooked and unrecognized. We give a robust definition for the…

Quantum Physics · Physics 2007-05-23 Berry Groisman , Dan Kenigsberg , Tal Mor

In this contribution we present a concise introduction to quantum entanglement in multipartite systems. After a brief comparison between bipartite systems and the simplest non-trivial multipartite scenario involving three parties, we review…

Quantum Physics · Physics 2024-09-10 Pawel Horodecki , Łukasz Rudnicki , Karol Życzkowski

We consider the problem of determining the state of a quantum system given one or more readings of the expectation value of an observable. The system is assumed to be a finite dimensional quantum control system for which we can influence…

Quantum Physics · Physics 2009-11-10 Domenico D'Alessandro

The sets of contexts and properties of a concept are embedded in the complex Hilbert space of quantum mechanics. States are unit vectors or density operators, and contexts and properties are orthogonal projections. The way calculations are…

Quantum Physics · Physics 2010-04-16 Diederik Aerts , Liane Gabora

Entanglement is a striking feature of quantum mechanics, and it has a key property called unextendibility. In this paper, we present a framework for quantifying and investigating the unextendibility of general bipartite quantum states.…

Quantum Physics · Physics 2024-03-28 Kun Wang , Xin Wang , Mark M. Wilde

In this paper, we investigate how to reduce the number of measurement configurations needed for sufficiently precise entanglement quantification. Instead of analytical formulae, we employ artificial neural networks to predict the amount of…

Quantum Physics · Physics 2022-07-20 Jan Roik , Karol Bartkiewicz , Antonín Černoch , Karel Lemr

There are at least a number of ways to formally define complexity. Most of them relate to some kind of minimal description of the studied object. Being this one in form of minimal resources of minimal effort needed to generate the object…

Quantum Physics · Physics 2013-04-25 Yuri Campbell , José Roberto Castilho Piqueira

Coherent states with large amplitudes are traditionally thought of as the best quantum mechanical approximation of classical behavior. Here we argue that, far from being classical, coherent state are in fact highly entangled. We demonstrate…

Quantum Physics · Physics 2007-05-23 D. Kaszlikowski , V. Vedral

A classification of multipartite entanglement in qubit systems is introduced for pure and mixed states. The classification is based on the robustness of the said entanglement against partial trace operation. Then we use current machine…

Quantum Physics · Physics 2022-10-17 F. El Ayachi , M. El Baz