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By using dynamical invariants theory, Hassoul et al. [1,2] investigate the quantum dynamics of two (2D) and three (3D) dimensional time-dependent coupled oscillators. They claim that, in the 2D case, introducing two pairs of annihilation…

Quantum Physics · Physics 2023-04-19 R. Zerimeche , N. Mana , M. Sekhri , N. Amaouche , M. Maamache

An appropriate extension of the effective potential theory is presented that permits the approximate calculation of the dynamical correlation functions for quantum systems. These are obtained by evaluating the generating functionals of the…

Statistical Mechanics · Physics 2007-05-23 A. Cuccoli , V. Tognetti , R. Giachetti , R. Vaia

A new variational approach for general relativity and modified theories of gravity is presented. In addition to the metric tensor, two independent affine connections enter the action as dynamical variables. In the matter action the…

General Relativity and Quantum Cosmology · Physics 2015-06-05 Nicola Tamanini

We propose that measurements of time-of-arrival correlations in multi-partite systems can sharply distinguish between different approaches to the time-of-arrival problem. To show this, we construct a Positive-Operator-Valued measure for two…

Quantum Physics · Physics 2017-03-15 Charis Anastopoulos , Ntina Savvidou

Time-varying optimization problems are central to many engineering applications, where performance metrics and system constraints evolve dynamically with time. Several algorithms have been proposed to address these problems; a common…

Optimization and Control · Mathematics 2025-10-28 Gianluca Bianchin , Bryan Van Scoy

Variational analysis provides the theoretical foundations and practical tools for constructing optimization algorithms without being restricted to smooth or convex problems. We survey the central concepts in the context of a concrete but…

Optimization and Control · Mathematics 2025-04-08 Johannes O. Royset

Tracking the solution of time-varying variational inequalities is an important problem with applications in game theory, optimization, and machine learning. Existing work considers time-varying games or time-varying optimization problems.…

Computer Science and Game Theory · Computer Science 2026-03-05 Hédi Hadiji , Sarah Sachs , Cristóbal Guzmán

We establish almost sure invariance principles, a strong form of approximation by Brownian motion, for non-stationary time-series arising as observations on dynamical systems. Our examples include observations on sequential expanding maps,…

Dynamical Systems · Mathematics 2014-06-18 N. Haydn , M. Nicol , A. Tôrôk , S. Vaienti

A careful analysis of differential renormalization shows that a distinguished choice of renormalization constants allows for a mathematically more fundamental interpretation of the scheme. With this set of a priori fixed integration…

High Energy Physics - Theory · Physics 2009-10-30 Oliver Schnetz

This chapter presents a self-contained approach of variational analysis and generalized differentiation to deriving necessary optimality in problems of bilevel optimization with Lipschitzian data. We mainly concentrate on optimistic models,…

Optimization and Control · Mathematics 2019-07-16 Boris S. Mordukhovich

We present a systematic method for dealing with time dependent quantum dynamics, based on the quantum brachistochrone and matrix mechanics. We derive the explicit time dependence of the Hamiltonian operator for a number of constrained…

Quantum Physics · Physics 2012-10-29 Peter G. Morrison

The method of the effective action for the composite operators $\Phi^2(x)$ and $\Phi^4(x)$ is applied to the termodynamics of the scalar quantum field with $\lambda\Phi^4$ interaction. An expansion of the finite temperature effective…

High Energy Physics - Theory · Physics 2015-06-26 Anna Okopińska

Multiscale dynamics are ubiquitous in applications of modern science. Because of time scale separation between relatively small set of slowly evolving variables and (typically) much larger set of rapidly changing variables, direct numerical…

Dynamical Systems · Mathematics 2016-04-08 Rafail V. Abramov

All covariant time operators with normalized probability distribution are derived. Symmetry criteria are invoked to arrive at a unique expression for a given Hamiltonian. As an application, a well known result for the arrival time…

Quantum Physics · Physics 2015-05-19 G. C. Hegerfeldt , J. G. Muga

Approximations of fractional Brownian motion using Poisson processes whose parameter sets have the same dimensions as the approximated processes have been studied in the literature. In this paper, a special approximation to the…

Statistics Theory · Mathematics 2012-01-05 Yuqiang Li , Hongshuai Dai

We study more general variational problems on time scales. Previous results are generalized by proving necessary optimality conditions for (i) variational problems involving delta derivatives of more than the first order, and (ii) problems…

Optimization and Control · Mathematics 2007-05-23 Rui A. C. Ferreira , Delfim F. M. Torres

We describe an ab initio and non-perturbative $R$-matrix with time-dependence theory for ultrafast atomic processes in light fields of arbitrary polarization. The theory is applicable to complex, multielectron atoms and atomic ions subject…

Atomic Physics · Physics 2018-12-04 D. D. A. Clarke , G. S. J. Armstrong , A. C. Brown , H. W. van der Hart

The simulation of systems that act on multiple time scales is challenging. A stable integration of the fast dynamics requires a highly accurate approximation whereas for the simulation of the slow part, a coarser approximation is accurate…

Numerical Analysis · Mathematics 2024-06-21 Sina Ober-Blöbaum , Theresa Wenger , Tobias Gail , Sigrid Leyendecker

In the setting of polynomial jump-diffusion dynamics, we provide an explicit formula for computing correlators, namely, cross-moments of the process at different time points along its path. The formula appears as a linear combination of…

Probability · Mathematics 2021-04-26 Fred Espen Benth , Silvia Lavagnini

Power laws in time and frequency appear in fields such as linear viscoelasticity and acoustics, viscous boundary layer problems, and dielectrics. This is consistent with fractional derivatives in the fundamental descriptions, since power…

General Physics · Physics 2023-08-16 Sverre Holm