English
Related papers

Related papers: Non-perturbative VEVs from a Local Expansion

200 papers

In this work, we systematically generalize the Evans function methodology to address vector systems of discrete equations. We physically motivate and mathematically use as our case example a vector form of the discrete nonlinear Schrodinger…

Pattern Formation and Solitons · Physics 2009-11-13 V. M. Rothos , P. G. Kevrekidis

In this letter we propose to use an extension of the variational approach known as Truncated Conformal Space to compute numerically the Vacuum Expectation Values of the operators of a conformal field theory perturbed by a relevant operator.…

High Energy Physics - Theory · Physics 2009-10-30 Riccardo Guida , Nicodemo Magnoli

Extended shallow water wave equations are derived, using the method of asymptotic expansions, from the Euler (or water wave) equations. These extended models are valid one order beyond the usual weakly nonlinear, long wave approximation,…

Fluid Dynamics · Physics 2022-05-11 Theodoros P. Horikis , Dimitrios J. Frantzeskakis , Noel F. Smyth

In this article we use an electromagnetic Lagrangian constructed so as to include dispersive effects in the description of an electromagnetic wave propagating in the Quantum Electrodynamic Vacuum. This Lagrangian is Lorentz invariant,…

High Energy Physics - Theory · Physics 2021-05-19 Francesco Pegoraro , Sergei Bulanov

The classical wave equation in the space of generalized functions (distributions)is considered. The Distributions Method of building the solutions of nonstationary boundary value problems (NBVP) for wave equations in coordinates spaces of…

Analysis of PDEs · Mathematics 2007-05-23 Lyudmila A. Alexeyeva

We propose a variational autoencoder (VAE) approach for parameter estimation in nonlinear mixed-effects models based on ordinary differential equations (NLME-ODEs) using longitudinal data from multiple subjects. In moderate dimensions,…

Methodology · Statistics 2026-02-11 Zhe Li , Mélanie Prague , Rodolphe Thiébaut , Quentin Clairon

The vacuum energy density is calculated for the $O(N)$ nonlinear sigma models in two dimensions. To obtain $\varepsilon_{vac}$ we assume that each point of the space in which non-perturbative f\/ields are determined can be replaced by a…

High Energy Physics - Theory · Physics 2009-10-28 V. G. Ksenzov

The sharp Wolff-type decoupling estimates of Bourgain--Demeter are extended to the variable coefficient setting. These results are applied to obtain new sharp local smoothing estimates for wave equations on compact Riemannian manifolds,…

Analysis of PDEs · Mathematics 2020-03-25 David Beltran , Jonathan Hickman , Christopher D. Sogge

We propose a novel neural network architecture that enables non-parametric calibration and generation of multivariate extreme value distributions (MEVs). MEVs arise from Extreme Value Theory (EVT) as the necessary class of models when…

Machine Learning · Statistics 2022-03-03 Ali Hasan , Khalil Elkhalil , Yuting Ng , Joao M. Pereira , Sina Farsiu , Jose H. Blanchet , Vahid Tarokh

We present the Complex Envelope Variable Approximation (CEVA) as the very useful and compact method for the analysis of the essentially nonlinear dynamical systems. It allows us to study both the stationary and non-stationary dynamics even…

Pattern Formation and Solitons · Physics 2020-04-20 Valeri V. Smirnov , Leonid I. Manevitch

We derive dispersion estimates for solutions of the one-dimensional discrete perturbed Schr\"odinger and wave equations. In particular, we improve upon previous works and weaken the conditions on the potentials. To this end we also provide…

Spectral Theory · Mathematics 2015-12-18 Iryna Egorova , Elena Kopylova , Gerald Teschl

Maxwell's equations in the vacuum can be formally cast in the form of Schr\"odinger's equation. Unfortunately, the vector to which this equation directly applies is not a wavefunction: its amplitude squared is not a probability density but…

Quantum Physics · Physics 2025-07-30 Stéphane Virally

Generalized linear latent variable models (GLLVMs) are a class of methods for analyzing multi-response data which has garnered considerable popularity in recent years, for example, in the analysis of multivariate abundance data in ecology.…

Methodology · Statistics 2021-07-07 Pekka Korhonen , Francis K. C. Hui , Jenni Niku , Sara Taskinen

We carry out the convergence analysis of the Scalar Auxiliary Variable (SAV) method applied to the nonlinear Schr\"odinger equation which preserves a modified Hamiltonian on the discrete level. We derive a weak and strong convergence…

Numerical Analysis · Mathematics 2021-07-07 Alexandre Poulain , Katharina Schratz

We derive various approximations for the solutions of nonlinear hyperbolic systems with fastly oscillating initial data. We first provide error estimates for the so-called slowly varying envelope, full dispersion, and Schr\"odinger…

Analysis of PDEs · Mathematics 2007-12-27 Mathieu Colin , David Lannes

A long-standing challenge encountered in modeling plasma dynamics is achieving practical Vlasov equation simulation in multiple spatial dimensions over large length and time scales. While direct multi-dimension Vlasov simulation methods…

Plasma Physics · Physics 2015-05-30 Harvey A. Rose , William Daughton

The learning and evaluation of energy-based latent variable models (EBLVMs) without any structural assumptions are highly challenging, because the true posteriors and the partition functions in such models are generally intractable. This…

Machine Learning · Computer Science 2021-06-08 Fan Bao , Kun Xu , Chongxuan Li , Lanqing Hong , Jun Zhu , Bo Zhang

The QED vacuum polarization in external monochromatic plane-wave electromagnetic fields is calculated with spatial and temporal variations of the external fields being taken into account. We develop a perturbation theory to calculate the…

High Energy Physics - Phenomenology · Physics 2019-12-06 Akihiro Yatabe , Shoichi Yamada

We consider one-dimensional difference Schroedinger equations on the discrete line with a potential generated by evaluating a real-analytic potential function V(x) on the one-dimensional torus along an orbit of the shift x-->x+nw. If the…

Dynamical Systems · Mathematics 2008-04-09 Michael Goldstein , Wilhelm Schlag

Variational autoencoders (VAEs), that are built upon deep neural networks have emerged as popular generative models in computer vision. Most of the work towards improving variational autoencoders has focused mainly on making the…

Machine Learning · Statistics 2016-11-17 Siddharth Agrawal , Ambedkar Dukkipati