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Simulations of quantum systems with Hamiltonian classical stochastic noise can be challenging when the noise exhibits temporal correlations over a multitude of time scales, such as for $1/f$ noise in solid-state quantum information…

Quantum Physics · Physics 2025-02-19 Tameem Albash , Steve Young , N. Tobias Jacobson

We study coarse pattern formation in a cellular automaton modelling a spatially-extended stochastic neural network. The model, originally proposed by Gong and Robinson [36], is known to support stationary and travelling bumps of localised…

Pattern Formation and Solitons · Physics 2016-10-10 Daniele Avitabile , Kyle Wedgwood

We study rare transitions in Markovian open quantum systems driven with Gaussian noise, applying transition path and interface sampling methods to trajectories generated by stochastic Schr\"odinger dynamics. Interface and path sampling…

Quantum Physics · Physics 2025-05-09 Robson Christie , Peter G. Bolhuis , David T. Limmer

Structure learning methods for covariance and concentration graphs are often validated on synthetic models, usually obtained by randomly generating: (i) an undirected graph, and (ii) a compatible symmetric positive definite (SPD) matrix. In…

Methodology · Statistics 2019-10-02 Irene Córdoba , Gherardo Varando , Concha Bielza , Pedro Larrañaga

We study regularizing effects of nonlinear stochastic perturbations for fully nonlinear PDE. More precisely, path-by-path $L^{\infty}$ bounds for the second derivative of solutions to such PDE are shown. These bounds are expressed as…

Probability · Mathematics 2018-05-08 Paul Gassiat , Benjamin Gess

Recently, variational quantum metrology was proposed for Hamiltonians with multiplicative parameters, wherein the estimation precision can be optimized via variational circuits. However, systems with generic Hamiltonians still lack these…

Quantum Physics · Physics 2023-09-25 Le Bin Ho

Modern distribution matching algorithms for training diffusion or flow models directly prescribe the time evolution of the marginal distributions between two boundary distributions. In this work, we consider a generalized distribution…

We demonstrate the phenomenon of stochastic resonance (SR) for discrete-time dynamical systems. We investigate various systems that are not necessarily bistable, but do have two well defined states, switching between which is aided by…

chao-dyn · Physics 2009-10-30 Prashant M. Gade , Renuka Rai , Harjinder Singh

We develop an estimator for the high-dimensional covariance matrix of a locally stationary process with a smoothly varying trend and use this statistic to derive consistent predictors in non-stationary time series. In contrast to the…

Methodology · Statistics 2020-01-08 Holger Dette , Weichi Wu

Identifying an appropriate covariance function is one of the primary interests in spatial and spatio-temporal statistics because it allows researchers to analyze the dependence structure of the random process. For this purpose, spatial…

Methodology · Statistics 2025-02-04 Jongwook Kim , Chunfeng Huang , Nicholas Bussberg

We consider estimation of covariance matrices and their inverses (a.k.a. precision matrices) for high-dimensional stationary and locally stationary time series. In the latter case the covariance matrices evolve smoothly in time, thus…

Statistics Theory · Mathematics 2014-01-07 Xiaohui Chen , Mengyu Xu , Wei Biao Wu

Covariance matrix tapers have a long history in signal processing and related fields. Examples of applications include autoregressive models (promoting a banded structure) or beamforming (widening the spectral null width associated with an…

Methodology · Statistics 2021-09-06 Esa Ollila , Arnaud Breloy

The paper studies identification of linear systems with multiplicative noise from multiple-trajectory data. An algorithm based on the least-squares method and multiple-trajectory data is proposed for joint estimation of the nominal system…

Systems and Control · Electrical Eng. & Systems 2022-06-07 Yu Xing , Benjamin Gravell , Xingkang He , Karl Henrik Johansson , Tyler Summers

In this paper, we present quantum algorithms for a class of highly-oscillatory transport equations, which arise in semiclassical computation of surface hopping problems and other related non-adiabatic quantum dynamics, based on the…

Numerical Analysis · Mathematics 2025-09-05 Anjiao Gu , Shi Jin

This paper is concerned with regularized extensions of hierarchical non-stationary temporal Gaussian processes (NSGPs) in which the parameters (e.g., length-scale) are modeled as GPs. In particular, we consider two commonly used NSGP…

Methodology · Statistics 2021-05-21 Zheng Zhao , Rui Gao , Simo Särkkä

This paper considers linear-quadratic control of a non-linear dynamical system subject to arbitrary cost. I show that for this class of stochastic control problems the non-linear Hamilton-Jacobi-Bellman equation can be transformed into a…

General Physics · Physics 2009-11-11 H. J. Kappen

We study a class of dynamical networks modeled by linear and time-invariant systems which are described by state-space realizations. For these networks, we investigate the relations between various types of factorizations which preserve the…

Systems and Control · Electrical Eng. & Systems 2025-12-02 Şerban Sabău , Andrei Sperilă , Cristian Oară , Ali Jadbabaie

A new method is presented which allows time averaged density matrices of closed quantum systems to be computed via a constraint overlap maximization. Due to its simplicity, this method can be combined with algorithms based on tensor…

Quantum Physics · Physics 2015-03-06 Volckmar Nebendahl

According to recent findings [1,2], empirical covariance matrices deduced from financial return series contain such a high amount of noise that, apart from a few large eigenvalues and the corresponding eigenvectors, their structure can…

Statistical Mechanics · Physics 2009-11-07 Szilard Pafka , Imre Kondor

We utilize the externally forced linearized Navier-Stokes equations to study the receptivity of pre-transitional boundary layers to persistent sources of stochastic excitation. Stochastic forcing is used to model the effect of free-stream…

Fluid Dynamics · Physics 2019-09-09 Wei Ran , Armin Zare , M. J. Philipp Hack , Mihailo R. Jovanović