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Selection of an ensemble of equally prepared quantum systems, based on measurements on it, is a basic step in quantum state purification. For an ensemble of single qubits, iterative application of selective dynamics has been shown to lead…

Quantum Physics · Physics 2007-05-23 T. Kiss , I. Jex , G. Alber , S. Vymetal

The relevance of chaos to evolution is discussed in the context of the origin and maintenance of diversity and complexity. Evolution to the edge of chaos is demonstrated in an imitation game. As an origin of diversity, dynamic clustering of…

adap-org · Physics 2008-02-03 Kunihiko Kaneko

Simple dynamical systems -- with a small number of degrees of freedom -- can behave in a complex manner due to the presence of chaos. Such systems are most often (idealized) limiting cases of more realistic situations. Isolating a small…

Chaotic Dynamics · Physics 2015-04-17 Temple He , Salman Habib

We study the dynamics of a "kicked" quantum system undergoing repeated measurements of momentum. A diffusive behavior is obtained for a large class of Hamiltonians, even when the dynamics of the classical counterpart is not chaotic. These…

Quantum Physics · Physics 2007-05-23 P. Facchi , S. Pascazio , A. Scardicchio

The model of an open Fermi-system is used for studying the interplay of intrinsic chaos and irreversible decay into open continuum channels. Two versions of the model are characterized by one-body chaos coming from disorder or by many-body…

Disordered Systems and Neural Networks · Physics 2014-03-31 S. Sorathia , F. M. Izrailev , G. L. Celardo , V. G. Zelevinsky , G. P. Berman

The harmonic oscillator is the paragon of physical models; conceptually and computationally simple, yet rich enough to teach us about physics on scales that span classical mechanics to quantum field theory. This multifaceted nature extends…

High Energy Physics - Theory · Physics 2021-02-10 Arpan Bhattacharyya , Wissam Chemissany , S. Shajidul Haque , Jeff Murugan , Bin Yan

As a model of decohering environment, we show that quantum chaotic system behave equivalently as many-body system. An approximate formula for the time evolution of the reduced density matrix of a system interacting with a quantum chaotic…

Quantum Physics · Physics 2009-04-24 Jayendra N. Bandyopadhyay

We study the relationship between quantum chaos and pseudorandomness by developing probes of unitary design. A natural probe of randomness is the "frame potential," which is minimized by unitary $k$-designs and measures the $2$-norm…

Quantum Physics · Physics 2017-05-24 Daniel A. Roberts , Beni Yoshida

Recent work has connected the type of fidelity decay in perturbed quantum models to the presence of chaos in the associated classical models. We demonstrate that a system's rate of fidelity decay under repeated perturbations may be measured…

Quantum Physics · Physics 2009-11-07 Joseph Emerson , Yaakov S. Weinstein , Seth Lloyd , D. G. Cory

We define quantum chaos and integrability in open quantum many-body systems as a dynamical property of single stochastic realizations, referred to as quantum trajectories. This definition relies on the predictions of random matrix theory…

A simple new binary test for chaos has been proposed by Gottwald and Melbourne. We apply this test successfully to the Henon-Heiles and Lorenz systems, demonstrating its applicability to conservative systems, as well as dissipative systems.…

Chaotic Dynamics · Physics 2007-05-23 John D. Barrow , Janna Levin

We investigate how quantum coherence can be distributed among the several off-diagonal elements of an arbitrary density matrix. An easily computable quantity that captures this variability notion is proposed and it is argued that it…

Quantum Physics · Physics 2026-04-24 Fernando Parisio

We investigate the sensitivity of quantum systems that are chaotic in a classical limit, to small perturbations of their equations of motion. This sensitivity, originally studied in the context of defining quantum chaos, is relevant to…

Quantum Physics · Physics 2009-11-07 Zbyszek P. Karkuszewski , Christopher Jarzynski , Wojciech H. Zurek

We propose a scheme to evaluate the amount of quantum discord and entanglement of formation for mixed states, and reveal their ordering relation via an intrinsic relationship between the two quantities distributed in different partners of…

Quantum Physics · Physics 2015-05-19 Li-Xiang Cen , Xin-Qi Li , JiuShu Shao , YiJing Yan

We revisit the problem of quantum bi- and multi-stability by considering the dissipative Double Resonance Model. For a large driving frequency, this system has a simpler phase structure than the driven dissipative nonlinear oscillator --…

Quantum Physics · Physics 2022-07-27 Andrey R. Kolovsky

With the development of low order scaling methods for performing Kohn-Sham Density Functional Theory, it is now possible to perform fully quantum mechanical calculations of systems containing tens of thousands of atoms. However, with an…

Chemical Physics · Physics 2020-04-03 William Dawson , Stephan Mohr , Laura E. Ratcliff , Takahito Nakajima , Luigi Genovese

Chaos and turbulence are complex physical phenomena, yet a precise definition of the complexity measure that quantifies them is still lacking. In this work we consider the relative complexity of chaos and turbulence from the perspective of…

Machine Learning · Computer Science 2023-07-21 Tim Whittaker , Romuald A. Janik , Yaron Oz

We investigate a quantum algorithm which simulates efficiently the quantum kicked rotator model, a system which displays rich physical properties, and enables to study problems of quantum chaos, atomic physics and localization of electrons…

Quantum Physics · Physics 2007-05-23 B. Levi , B. Georgeot , D. L. Shepelyansky

We developed a powerful computational approach to elaborate on onset mechanisms of deterministic chaos due to complex homoclinic bifurcations in diverse systems. Its core is the reduction of phase space dynamics to symbolic binary…

Chaotic Dynamics · Physics 2018-11-07 Krishna Pusuluri , Andrey L Shilnikov

We demonstrate that the long-time dynamics of an observable associated with a single lattice site is sufficient to determine whether a many-body quantum system exhibits level statistics characteristic of random matrix theory, a widely used…

Statistical Mechanics · Physics 2025-10-20 Isaías Vallejo-Fabila , Adway Kumar Das , Sayan Choudhury , Lea F. Santos