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We perform a model-independent investigation of the thermodynamic evolution of the Universe by reconstructing the expansion history from observational data using Gaussian Process regression. We consider three independent combinations of…

Cosmology and Nongalactic Astrophysics · Physics 2026-04-22 Afaq Maqsood , Tanima Duary

While algebraic derivations establish theoretical limits for quantum cloning, practical implementations require explicit operator representations that are often unavailable analytically. We present a computational framework that…

Quantum Physics · Physics 2026-05-21 Jörg Hettel

A semiclassical approximation for an evolving density operator, driven by a "closed" hamiltonian operator and "open" markovian Lindblad operators, is obtained. The theory is based on the chord function, i.e. the Fourier transform of the…

Quantum Physics · Physics 2020-08-18 A. M. Ozorio de Almeida , P. de M. Rios , O. Brodier

Correlations between different partitions of quantum systems play a central role in a variety of many-body quantum systems, and they have been studied exhaustively in experimental and theoretical research. Here, we investigate dynamical…

The efficiency of time dependent density matrix renormalization group methods is intrinsically connected with the rate of entanglement growth. We introduce a new measure of entanglement in the space of operators and show, for transverse…

Quantum Physics · Physics 2009-03-04 Tomaz Prosen , Iztok Pizorn

We have extended the ANTARES code to simulate the coupling of pulsation with convection in Cepheid-like variables in an increasingly realistic way, in particular in multidimensions, 2D at this stage. Present days models of radially…

Solar and Stellar Astrophysics · Physics 2014-03-12 Eva Mundprecht , Herbert J. Muthsam , Friedrich Kupka

We study the transition from the full quantum mechanical description of physical systems to an approximate classical stochastic one. Our main tool is the identification of the closed-time-path (CTP) generating functional of Schwinger and…

General Relativity and Quantum Cosmology · Physics 2016-08-31 Charis Anastopoulos

Efficient coordination for collective spatial distribution is a fundamental challenge in multi-agent systems. Prior research on Density-Driven Optimal Control (D2OC) established a framework to match agent trajectories to a desired spatial…

Optimization and Control · Mathematics 2026-03-20 Julian Martinez , Kooktae Lee

Sparsity is a ubiquitous feature of many real world signals such as natural images and neural spiking activities. Conventional compressed sensing utilizes sparsity to recover low dimensional signal structures in high ambient dimensions…

Statistics Theory · Mathematics 2018-07-02 Abbas Kazemipour

Our main goal in this paper is to extend to any system of coupled quadratic Hamiltonians some properties known for systems of quantum harmonic oscillators related with the Brownian Quantum Motion model. In a first part we get a rather…

Mathematical Physics · Physics 2012-11-19 Didier Robert

We present a numerical method for studying the real time dynamics of a small interacting quantum system coupled to an infinite fermionic reservoir. By building an orthonormal basis in the operator space, we turn the Heisenberg equation of…

Strongly Correlated Electrons · Physics 2013-12-17 Pei Wang

Commonly, the notion of "quantum chaos'' refers to the fast scrambling of information throughout complex quantum systems undergoing unitary evolution. Motivated by the Krylov complexity and the operator growth hypothesis, we demonstrate…

Quantum Physics · Physics 2024-09-19 Eoin Carolan , Anthony Kiely , Steve Campbell , Sebastian Deffner

Quantum states in complex aggregates are unavoidably affected by environmental effects, which typically cannot be accurately modeled by simple Markovian processes. As system sizes scale up, nonperturbative simulation become thus unavoidable…

Statistical Mechanics · Physics 2024-06-26 Meng Xu , J. T. Stockburger , J. Ankerhold

Having a broad range of methods available for implementing unitary operations is crucial for quantum information tasks. We study a dissipative process commonly used to describe dissipatively coupled systems and show that the process can…

Quantum Physics · Physics 2020-02-12 C. Arenz , A. Metelmann

Dynamics of an open $N$-state quantum system is typically modeled with a Markovian master equation describing the evolution of the system's density operator. By using generators of $SU(N)$ group as a basis, the density operator can be…

Quantum Physics · Physics 2019-11-20 A. Liniov , I. Meyerov , E. Kozinov , V. Volokitin , I. Yusipov , M. Ivanchenko , S. Denisov

We find the time evolution of the system of two non-interacting unstable particles, distinguishable as well as identical ones, in arbitrary reference frame having only the Kraus operators governing the evolution of its components in the…

Quantum Physics · Physics 2010-04-05 P. Caban , J. Rembielinski , K. A. Smolinski , Z. Walczak , M. Wlodarczyk

We consider open quantum systems with factorized initial states, providing the structure of the reduced system dynamics, in terms of environment cumulants. We show that such completely positive (CP) and trace preserving (TP) maps can be…

Quantum Physics · Physics 2018-10-11 Giulio Gasbarri , Luca Ferialdi

An original method to exactly solve the non-Markovian Master Equation describing the interaction of a single harmonic oscillator with a quantum environment in the weak coupling limit is reported. By using a superoperatorial approach we…

Quantum Physics · Physics 2009-11-07 F. Intravaia , S. Maniscalco , A. Messina

Given the ubiquity of non-separable optimization problems in real worlds, in this paper we analyze and extend the large-scale version of the well-known cooperative coevolution (CC), a divide-and-conquer black-box optimization framework, on…

Neural and Evolutionary Computing · Computer Science 2024-10-14 Qiqi Duan , Chang Shao , Guochen Zhou , Haobin Yang , Qi Zhao , Yuhui Shi

To mitigate dissipative effects from environmental interactions and efficiently stabilize quantum states, time-optimal control has emerged as an effective strategy for open quantum systems. This paper extends the framework by incorporating…

Quantum Physics · Physics 2025-08-25 Yunyan Lee , Ian R. Petersen , Daoyi Dong