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Recent results by Harrow et. al. and by Ta-Shma, suggest that quantum computers may have an exponential advantage in solving a wealth of linear algebraic problems, over classical algorithms. Building on the quantum intuition of these…

Quantum Physics · Physics 2017-04-07 Michael Ben-Or , Lior Eldar

Albert and Callender have challenged the received view that theories like classical electrodynamics and non-relativistic quantum mechanics are time reversal invariant. They claim that time reversal should correspond to the mere reversal of…

History and Philosophy of Physics · Physics 2025-10-30 Ward Struyve

We extend a contraction mapping argument for ordinary state-dependent delay differential equations to evolutionary partial differential equations in the sense of R. Picard, that is, to equations of the form $\bigl(\partial_{t}…

Analysis of PDEs · Mathematics 2025-11-20 Bernhard Aigner , Marcus Waurick

If a higher derivative theory arises from a transformation of variables that involves time derivatives, a tailor-made Hamiltonian formulation is shown to exist. The details and advantages of this elegant Hamiltonian formulation, which…

Mathematical Physics · Physics 2019-06-05 Hans Christian Öttinger

In this work, we extend the concept of Robinson spaces to asymmetric dissimilarities, enhancing their applicability in representing and analyzing complex data. Within this generalized framework, we introduce two different problems that…

Discrete Mathematics · Computer Science 2024-12-06 Francois Brucker , Pascal Préa , Christopher Thraves Caro

Fractional mechanics describes both conservative and non-conservative systems. The fractional variational principles gained importance in studying the fractional mechanics and several versions are proposed. In classical mechanics the…

Mathematical Physics · Physics 2007-08-14 Dumitru Baleanu , Sami I. Muslih , Eqab M. Rabei

A generalised form of time-translation-invariance permits to re-derive the known generic phenomenology of ageing, which arises in classical many-body systems after a quench from an initially disordered system to a temperature $T\leq T_c$,…

Statistical Mechanics · Physics 2025-05-30 Malte Henkel

We introduce and study here a renewal process defined by means of a time-fractional relaxation equation with derivative order $\alpha(t)$ varying with time $t\geq0$. In particular, we use the operator introduced by Scarpi in the Seventies…

Probability · Mathematics 2023-03-28 Luisa Beghin , Lorenzo Cristofaro , Roberto Garrappa

A method based off of operator consideration for solving the time evolution of a wave function is developed. The method is applied to free space, constant force and harmonic oscillator potentials where general solutions are derived for the…

Quantum Physics · Physics 2012-08-14 K. P. Michnicki

In conventional machine learning applications, each data attribute is assumed to be orthogonal to others. Namely, every pair of dimension is orthogonal to each other and thus there is no distinction of in-between relations of dimensions.…

Computer Vision and Pattern Recognition · Computer Science 2020-06-16 Yigit Oktar , Mehmet Turkan

Introduced more than a half century ago, Granger causality has become a popular tool for analyzing time series data in many application domains, from economics and finance to genomics and neuroscience. Despite this popularity, the validity…

Methodology · Statistics 2021-05-10 Ali Shojaie , Emily B. Fox

The time-convolutionless master equation provides a general framework to model non-Markovian dynamics of an open quantum system with a time-local generator. A diagrammatic representation is developed and proven for the perturbative…

Quantum Physics · Physics 2023-10-19 Bing Gu

We consider a class of Lagrangians that depend not only on some configurational variables and their first time derivatives, but also on second time derivatives, thereby leading to fourth-order evolution equations. The proposed higher-order…

Mathematical Physics · Physics 2019-01-10 Hans Christian Öttinger

In this and a companion paper, we show that quantum field theories with gauge symmetries permit a broader class of classical dynamics than typically assumed. In this article, we show that the dynamics extracted from the path integral or…

High Energy Physics - Theory · Physics 2023-05-04 David E. Kaplan , Tom Melia , Surjeet Rajendran

In the covariant canonical approach to classical physics, each point in phase space represents an entire classical trajectory. Initial data at a fixed time serve as coordinates for this ``timeless'' phase space, and time evolution can be…

General Relativity and Quantum Cosmology · Physics 2023-12-25 S. Carlip , Weixuan Hu

This work proposes a Bayesian inference method for the reduced-order modeling of time-dependent systems. Informed by the structure of the governing equations, the task of learning a reduced-order model from data is posed as a Bayesian…

Numerical Analysis · Mathematics 2023-01-18 Mengwu Guo , Shane A. McQuarrie , Karen E. Willcox

The Makespan Scheduling problem is an extensively studied NP-hard problem, and its simplest version looks for an allocation approach for a set of jobs with deterministic processing times to two identical machines such that the makespan is…

Neural and Evolutionary Computing · Computer Science 2025-04-25 Feng Shi , Daoyu Huang , Xiankun Yan , Frank Neumann

In this work we look at the original fractional calculus of variations problem in a somewhat different way. As a simple consequence, we show that a fractional generalization of a classical problem has a solution without any restrictions on…

Optimization and Control · Mathematics 2019-08-27 Rui A. C. Ferreira

Relations between integrals of time-ordered product of operators, and their representation in terms of energy-ordered products are studied. Both can be decomposed into irreducible factors and these relations are discussed as well. The…

High Energy Physics - Phenomenology · Physics 2015-06-25 C. S. Lam

A general formlulation for discrete-time quantum mechanics, based on Feynman's method in ordinary quantum mechanics, is presented. It is shown that the ambiguities present in ordinary quantum mechanics (due to noncommutativity of the…

Quantum Physics · Physics 2015-06-26 M. Khorrami