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In this work, multi-variable derivative-free optimization algorithms for unconstrained optimization problems are developed. A novel procedure for approximating the gradient of multi-variable objective functions based on non-commutative maps…

Optimization and Control · Mathematics 2021-11-17 Jan Feiling , Mohamed-Ali Belabbas , Christian Ebenbauer

We provide the set of equations for non-relativistic fluid dynamics on arbitrary, possibly time-dependent spaces, in general coordinates. These equations are fully covariant under either local Galilean or local Carrollian transformations,…

High Energy Physics - Theory · Physics 2018-07-18 Luca Ciambelli , Charles Marteau , Anastasios C. Petkou , P. Marios Petropoulos , Konstantinos Siampos

We define a time-dependent extension of the quantum geometric tensor to describe the geometry of the time-parameter space for a quantum state, by considering small variations in both time and wave function parameters. Compared to the…

Quantum Physics · Physics 2025-02-05 Bogar Díaz , Diego Gonzalez , Marcos J. Hernández , J. David Vergara

Time-dependent calculation has been a suitable method to investigate the quantum dynamical processes. In Ref. [1] = [T. Oishi et al., J. of Phys. G 45, 105101 (2018)], we applied this method to the one-dimensional two-fermion tunneling in…

Nuclear Theory · Physics 2018-10-17 Tomohiro Oishi

We consider a finite difference approximation of mean curvature flow for axisymmetric surfaces of genus zero. A careful treatment of the degeneracy at the axis of rotation for the one dimensional partial differential equation for a…

Numerical Analysis · Mathematics 2021-10-20 Klaus Deckelnick , Robert Nürnberg

Because reinforcement learning suffers from a lack of scalability, online value (and Q-) function approximation has received increasing interest this last decade. This contribution introduces a novel approximation scheme, namely the Kalman…

Machine Learning · Computer Science 2014-06-13 Matthieu Geist , Olivier Pietquin

We propose a new approach to represent nonparametrically the linear dependence structure of a spatio-temporal process in terms of latent common factors. Though it is formally similar to the existing reduced rank approximation methods…

Methodology · Statistics 2018-03-20 Da Huang , Qiwei Yao , Rongmao Zhang

These are expanded lecture notes of a mini-course whose objectives were to introduce the basic concepts, constructions and techniques of noncommutative geometry, as well as their uses as a framework for modelling quantum spacetime. Key…

High Energy Physics - Theory · Physics 2025-12-08 Richard J. Szabo

Traditional derivation of the material time derivative of volume, surface, and line integrals relies upon the notion of a referential configuration of continuum. Such a notion, however, is artificial and, probably, somewhat misleading in…

Fluid Dynamics · Physics 2008-07-23 K. Y. Volokh

In arXiv:2205.02920 a variant of the classical elastic flow for closed curves in $\mathbb{R}^{n}$ was introduced, that is more suitable for numerical purposes. Here we investigate the long-time properties of such evolution demonstrating…

Analysis of PDEs · Mathematics 2023-04-05 Paola Pozzi

We study stochastic Amari-type neural field equations, which are mean-field models for neural activity in the cortex. We prove that under certain assumptions on the coupling kernel, the neural field model can be viewed as a gradient flow in…

Analysis of PDEs · Mathematics 2019-11-11 Christian Kuehn , Jonas M. Tölle

The paper considers a thermodynamically consistent phase-field model of a two-phase flow of incompressible viscous fluids. The model allows for a non-linear dependence of fluid density on the phase-field order parameter. Driven by…

Numerical Analysis · Mathematics 2023-09-27 Yerbol Palzhanov , Alexander Zhiliakov , Annalisa Quaini , Maxim Olshanskii

We prove optimal error bounds for a second order in time finite element approximation of curve shortening flow in possibly higher codimension. In addition, we introduce a second order in time method for curve diffusion. Both schemes are…

Numerical Analysis · Mathematics 2026-01-29 Klaus Deckelnick , Robert Nürnberg

We consider the case of a deformable material interface between two immiscible moving media, both of them being magnetiable. The time dependence of the metric at the interface introduces a non linear term, proportional to the mean…

Fluid Dynamics · Physics 2015-05-14 Q. Vanhaelen , M. Hennenberg , S. Slavtchev , B. Weyssow

We explicitly construct parameter transformations between gradient flows in metric spaces, called curves of maximal slope, having different exponents when the associated function satisfies a suitable convexity condition. These…

Analysis of PDEs · Mathematics 2024-04-04 Sho Shimoyama

A recently proposed schematic model for the non--linear rheology of dense colloidal dispersions is compared to flow curves measured in suspensions that consist of thermosensitive particles. The volume fraction of this purely repulsive model…

Soft Condensed Matter · Physics 2009-11-11 Matthias Fuchs , Matthias Ballauff

We develop an arithmetic analogue of linear partial differential equations in two independent ``space-time'' variables. The spatial derivative is a Fermat quotient operator, while the time derivative is the usual derivation. This allows us…

Analysis of PDEs · Mathematics 2007-05-23 Alexandru Buium , Santiago R. Simanca

We prove the existence of semiorthogonal decompositions of derived categories of Quot schemes of zero-dimensional quotients on curves in terms of derived categories of symmetric products of curves. The above result is a categorical analogue…

Algebraic Geometry · Mathematics 2022-07-21 Yukinobu Toda

This work proposes an algorithmic framework to learn time-varying graphs from online data. The generality offered by the framework renders it model-independent, i.e., it can be theoretically analyzed in its abstract formulation and then…

Machine Learning · Computer Science 2022-05-25 Alberto Natali , Elvin Isufi , Mario Coutino , Geert Leus

We generalize the theory of flow equations to open quantum systems focusing on Lindblad master equations. We introduce and discuss three different generators of the flow that transform a linear non-Hermitian operator into a diagonal one. We…

Quantum Physics · Physics 2020-12-30 Lorenzo Rosso , Fernando Iemini , Marco Schirò , Leonardo Mazza