Publications associées à Hamilton's principle

WILD SOLUTIONS TO SCALAR EULER-LAGRANGE EQUATIONS

. We study very weak solutions to scalar Euler-Lagrange equations associated with quadratic convex functionals. We investigate whether W1,1 solutions are necessarily W 1,2 Nash and Schauder applicable. We answer this question positively for a suitable clas ...

Amer Mathematical Soc2024

How Lagrangian States Evolve Into Random Waves

Alejandro Rivera

In this paper, we consider a compact connected manifold (X, g) of negative curvature, and a family of semi-classical Lagrangian states f(h)(x) = a(x)e(i phi(x)/h) on X. For a wide family of phases phi, we show that f(h), when evolved by the semi-classical ...

ECOLE POLYTECHNIQUE2022

Adaptive Stochastic Variance Reduction for Non-convex Finite-Sum Minimization

Volkan Cevher, Kimon Antonakopoulos, Efstratios Panteleimon Skoulakis, Leello Tadesse Dadi, Ali Kavis

We propose an adaptive variance-reduction method, called AdaSpider, for minimization of L-smooth, non-convex functions with a finite-sum structure. In essence, AdaSpider combines an AdaGrad-inspired [Duchi et al., 2011, McMahan & Streeter, 2010], but a fai ...

2022

An efficient quantum algorithm for the time evolution of parameterized circuits

Giuseppe Carleo, Filippo Vicentini, Stefano Barison

We introduce a novel hybrid algorithm to simulate the real-time evolution of quantum systems using parameterized quantum circuits. The method, named "projected - Variational Quantum Dynamics" (p-VQD) realizes an iterative, global projection of the exact ti ...

VEREIN FORDERUNG OPEN ACCESS PUBLIZIERENS QUANTENWISSENSCHAF2021

A gyrokinetic model for the plasma periphery of tokamak devices

Paolo Ricci, Paolo De Los Rios, Rogério Manuel Cabete De Jesus Jorge, Baptiste Jimmy Frei

A gyrokinetic model is presented that can properly describe large and small amplitude electromagnetic fluctuations occurring on scale lengths ranging from the electron Larmor radius to the equilibrium perpendicular pressure gradient scale length, and the a ...

Cambridge University Press2020

Multithermal-Multibaric Molecular Simulations from a Variational Principle

Pablo Miguel Piaggi, Michele Parrinello

We present a method for performing multithermal-multibaric molecular dynamics simulations that sample entire regions of the temperature-pressure (TP) phase diagram. The method uses a variational principle [Valsson and Parrinello, Phys. Rev. Lett. 113, 0906 ...

2019

Axisymmetric Tokamak Equilibria computed with a Predefined Safety Factor Profile as CHEASE input

Olivier Sauter, Antoine Pierre Emmanuel Alexis Merle

The CHEASE code, which has been developed at the Swiss Plasma Center, generates an accurate reconstruction of toroidal magnetohydrodynamics equilibria by numerically solving the Grad-Shafranov equation. Having demonstrated its ability to achieve good conve ...

2016

Force-based higher-order beam element with flexural-shear-torsional interaction in 3D frames. Part II: Applications

João Saraiva Esteves Pacheco de Almeida

The specific features of the proposed force-based formulation derived in the companion paper, which is applied for the first time to higher-order beam theories, are herein thoroughly validated. Introductory numerical examples illustrate the influence of me ...

Elsevier2015

Existence and conditional energetic stability of three-dimensional fully localised solitary gravity-capillary water waves

Boris Buffoni

In this paper we show that the hydrodynamic problem for three-dimensional water waves with strong surface-tension effects admits a fully localised solitary wave which decays to the undisturbed state of the water in every horizontal direction. The proof is ...

Academic Press Inc Elsevier Science2013

Reduced Variational Formulations in Free Boundary Continuum Mechanics

Tudor Ratiu, François Gay-Balmaz

We present the material, spatial, and convective representations for elasticity and fluids with a free boundary from the Lagrangian reduction point of view, using the material and spatial symmetries of these systems. The associated constrained variational ...

Springer-Verlag2012

Euler-Poincare Formulation Of Hybrid Plasma Models

Cesare Tronci

Three different hybrid Vlasov-fluid systems are derived by applying reduction by symmetry to Hamilton's variational principle. In particular, the discussion focuses on the Euler-Poincare formulation of three major hybrid MHD models, which are compared in t ...

2012

Lagrange-Poincare field equations

Tudor Ratiu, François Gay-Balmaz

The Lagrange-Poincare equations of classical mechanics are cast into a field theoretic context together with their associated constrained variational principle. An integrability/reconstruction condition is established that relates solutions of the original ...

2011

A Hamilton-Jacobi Formulation for Cooperative Control of Multi-Agent Systems

Denis Gillet, Sylvain Rudaz, Hajir Roozbehani

Coordination of autonomous non-point agents is studied in this work. Interactions between vehicles together with their internal dynamics have been modeled as a continuous, unconstrained differential game. In particular, collision prediction is shown to be ...

2009

Moment approach to the bootstrap current in nonaxisymmetric toroidal plasmas using deltaf Monte Carlo methods

Wilfred Anthony Cooper, Trach-Minh Tran

To evaluate the bootstrap current in nonaxisymmetric toroidal plasmas quantitatively, a deltaf Monte Carlo method is incorporated into the moment approach. From the drift-kinetic equation with the pitch-angle scattering collision operator, the bootstrap cu ...

American Institute of Physics (AIP)2009

Comment on « Angular distributions of H-induced HD and D2 desorptions from the Si(100) surfaces » [J. Chem. Phys. 124, 054715 (2006)]

Régis Bisson

In their article, Inanaga et al. have presented an angular distribution for the desorption of hydrogen molecules induced by hydrogen atoms impinging on a hydrogenated Si(100) surface and compared the measurement with classical trajectory calculations based ...

2008