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In this paper, we first introduce a new spatial-temporal interaction operator to describe the space-time dependent phenomena. Then we consider the stochastic optimal control of a new system governed by a stochastic partial differential…

Optimization and Control · Mathematics 2020-03-06 Zhun Gou , Nan-jing Huang , Ming-hui Wang , Yao-jia Zhang

Classical dynamical laws are conventionally formulated as closed evolution equations defined on fixed geometric backgrounds and a global time parameter. We develop a formulation in which neither prescribed evolution laws nor an external…

General Physics · Physics 2026-04-17 Gunjan Auti , Hirofumi Daiguji , Gouhei Tanaka

Based on recently derived exact stochastic Liouville-von Neumann equations, several strategies for the efficient simulation of open quantum systems are developed and tested on the spin-boson model. The accuracy and efficiency of these…

Condensed Matter · Physics 2007-05-23 J. T. Stockburger

Space-time correlation functions constitute a useful instrument from the research toolkit of continuous-media and many-body physics. We adopt here this concept for single-particle random walks and demonstrate that the corresponding…

Statistical Mechanics · Physics 2013-04-30 V. Zaburdaev , S. Denisov , P. Hanggi

Fine particulate matter (PM$_{2.5}$) has become a great concern worldwide due to its adverse health effects. PM$_{2.5}$ concentrations typically exhibit complex spatio-temporal variations. Both the mean and the spatio-temporal dependence…

Methodology · Statistics 2022-02-25 Ghulam A. Qadir , Ying Sun

A study on the notion of covariant derivatives in flat and curved space-time via It\^o-Wiener processes, when subjected to stochastic processes, is presented. Going into details, there is an analysis of the following topics: (i) Besov…

Probability · Mathematics 2023-04-26 Edoardo Niccolai

Environmental and climate processes are often distributed over large space-time domains. Their complexity and the amount of available data make modelling and analysis a challenging task. Statistical modelling of environment and climate data…

Methodology · Statistics 2019-10-02 Behnaz Pirzamanbein

Stochastic evolution underpins several approaches to the dynamics of open quantum systems, such as random modulation of Hamiltonian parameters, the stochastic Schrodinger equation (SSE), and the stochastic Liouville equation (SLE). These…

Quantum Physics · Physics 2026-01-22 Pietro De Checchi , Federico Gallina , Barbara Fresch , Giulio G. Giusteri

We study covariant models for vacuum spherical gravity within a canonical setting. Starting from a general ansatz, we derive the most general family of Hamiltonian constraints that are quadratic in first-order and linear in second-order…

General Relativity and Quantum Cosmology · Physics 2024-10-04 Asier Alonso-Bardaji , David Brizuela

In loop quantum cosmology, non-perturbative quantum gravity effects lead to the resolution of the big bang singularity by a quantum bounce without introducing any new degrees of freedom. Though fundamentally discrete, the theory admits a…

General Relativity and Quantum Cosmology · Physics 2010-05-12 Gonzalo J. Olmo , Parampreet Singh

A recently proposed stochastic hidden variable model for quantum mechanics has been claimed to involve "retrocausality" due to the appearance of equations of motion with future-time boundary conditions. We formulate an equivalent system of…

Quantum Physics · Physics 2025-12-05 William S. DeWitt , Benjamin H. Feintzeig

Motivated by recent problems in mathematical cosmology, in which temporal averaging methods are applied in order to analyze the future asymptotics of models which exhibit oscillatory behavior, we provide a theorem concerning the large-time…

Dynamical Systems · Mathematics 2021-03-03 David Fajman , Gernot Heißel , Jin Woo Jang

The problem of broad practical interest in spatiotemporal data analysis, i.e., discovering interpretable dynamic patterns from spatiotemporal data, is studied in this paper. Towards this end, we develop a time-varying reduced-rank vector…

Machine Learning · Computer Science 2022-11-29 Xinyu Chen , Chengyuan Zhang , Xiaoxu Chen , Nicolas Saunier , Lijun Sun

A relation expressing the covariant transformation properties of a relativistic position operator is derived. This relation differs from the one existing in the literature expressing manifest covariance by some factor ordering. The relation…

General Relativity and Quantum Cosmology · Physics 2007-05-23 J. Mourad

Inference of fields defined in space and time from observational data is a core discipline in many scientific areas. This work approaches the problem in a Bayesian framework. The proposed method is based on statistically homogeneous random…

Data Analysis, Statistics and Probability · Physics 2021-05-05 Philipp Frank , Reimar Leike , Torsten A. Enßlin

Space-time fractional evolution equations are a powerful tool to model diffusion displaying space-time heterogeneity. We prove existence, uniqueness and stochastic representation of classical solutions for an extension of Caputo evolution…

Analysis of PDEs · Mathematics 2018-09-03 Lorenzo Toniazzi

The Hamiltonian approach to cosmological perturbations in general relativity in finite space-time is developed, where a cosmological scale factor is identified with spatial averaging the metric determinant logarithm. This identification…

High Energy Physics - Theory · Physics 2009-11-11 B. M. Barbashov , V. N. Pervushin , A. F. Zakharov , V. A. Zinchuk

A Gaussian operator basis provides a means to formulate phase-space simulations of the real- and imaginary-time evolution of quantum systems. Such simulations are guaranteed to be exact while the underlying distribution remains…

Computational Physics · Physics 2012-04-04 M. Ogren , K. V. Kheruntsyan , J. F. Corney

We present a general and model-independent method to obtain an effective Markovian quantum kinetic equation for the expectation value of a slowly evolving scalar field in an adiabatically evolving background from first principles of…

High Energy Physics - Phenomenology · Physics 2022-05-25 Gilles Buldgen , Marco Drewes , Jin U Kang , Ui Ri Mun

The aim of this paper is two-fold: in probing the statistical mechanical properties of interacting quantum fields, and in providing a field theoretical justification for a stochastic source term in the Boltzmann equation. We start with the…

High Energy Physics - Phenomenology · Physics 2008-11-26 Esteban Calzetta , Bei Lok Hu
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