Search results for "Classical physics"
showing 10 items of 190 documents
Rigidity of quasisymmetric mappings on self-affine carpets
2016
We show that the class of quasisymmetric maps between horizontal self-affine carpets is rigid. Such maps can only exist when the dimensions of the carpets coincide, and in this case, the quasisymmetric maps are quasi-Lipschitz. We also show that horizontal self-affine carpets are minimal for the conformal Assouad dimension.
Signatures of physical constraints in rotating rigid bodies
2023
We study signatures of physical constraints on free rotations of rigid bodies. We show analytically that the physical or non-physical nature of the moments of inertia of a system can be detected by qualitative changes both in the Montgomery Phase and in the Tennis Racket Effect.
The classical concept of mass: theoretical difficulties and students’ definitions
1993
An analysis of the concepts of mass in classical physics on the basis of their historical, philosophical and semantic connotations is given. A classification of the most current definitions of mass is proposed from its physical representation and topic area. The definitions of mass, and some related issues, given by several groups of secondary school students are analysed. The results seem to confirm a generalized qualitative‐teleological view of scientific concepts in contrast to the more orthodox formal‐quantitative formulation of physics.
Modeling of solids
2022
This text is the support for the course of Modeling of Solids, of the Master of Mechanics of the University Paris-Saclay - Curriculum MMM: Mathematical Methods for Mechanics, held at Versailles. The course is the continuation of the course Continuum Mechanics - Solids, and as such it is an introduction, for graduate students, to some typical topics of the theory of solid bodies. The different arguments are dealt with in a simple, succinct way, the objective being to give to students the fundamentals of each argument. Only static problems are considered, being the dynamic of structures dealt with in other courses.
Crack bifurcations in a strained lattice
1996
Dynamic crack propagation in a strained, granular, and brittle material is investigated by modeling the material as a lattice network of elastic beams. By tuning the strain and the ratio of axial to bending stiffness of the beams, a crack propagates either straight, or it branches, or it bifurcates. The crack tip velocity is calculated approximately for cracks that propagate straight. In a bifurcated crack the number of broken beams follows a scaling law. The shape of the branches is found to be the same as in recent experiments.
Numerical Study of the semiclassical limit of the Davey-Stewartson II equations
2014
We present the first detailed numerical study of the semiclassical limit of the Davey–Stewartson II equations both for the focusing and the defocusing variant. We concentrate on rapidly decreasing initial data with a single hump. The formal limit of these equations for vanishing semiclassical parameter , the semiclassical equations, is numerically integrated up to the formation of a shock. The use of parallelized algorithms allows one to determine the critical time tc and the critical solution for these 2 + 1-dimensional shocks. It is shown that the solutions generically break in isolated points similarly to the case of the 1 + 1-dimensional cubic nonlinear Schrodinger equation, i.e., cubic…
A WAVELET OPERATOR ON THE INTERVAL IN SOLVING MAXWELL'S EQUATIONS
2011
In this paper, a differential wavelet-based operator defined on an interval is presented and used in evaluating the electromagnetic field described by Maxwell's curl equations, in time domain. The wavelet operator has been generated by using Daubechies wavelets with boundary functions. A spatial differential scheme has been performed and it has been applied in studying electromagnetic phenomena in a lossless medium. The proposed approach has been successfully tested on a bounded axial-symmetric cylindrical domain.
First-principles calculation of electron spin-rotation tensors.
2010
Using Curl's Hamiltonian (Curl, R. F. Mol. Phys. 1965, 9, 585) first-principles calculations at the Hartree-Fock and various coupled-cluster (CC) levels based on a perturbative scheme are reported. The effects of basis-set dependence and electron correlation have been investigated by performing benchmark calculations for a set of radicals comprising 12 species and 14 electronic states. In comparison to experimental results, the electron spin-rotation tensor is obtained with a 10-15% accuracy when using the CC singles and doubles approximation and a triple-zeta quality basis set. Some improvements are seen when triple excitations are considered via the CC singles, doubles, and triples model.
Quadrupole deformation of Xe-130 measured in a Coulomb-excitation experiment
2020
Physical review / C 102(5), 054304 (2020). doi:10.1103/PhysRevC.102.054304
Accurate expansion of cylindrical paraxial waves for its straightforward implementation in electromagnetic scattering
2017
Abstract The evaluation of vector wave fields can be accurately performed by means of diffraction integrals, differential equations and also series expansions. In this paper, a Bessel series expansion which basis relies on the exact solution of the Helmholtz equation in cylindrical coordinates is theoretically developed for the straightforward yet accurate description of low-numerical-aperture focal waves. The validity of this approach is confirmed by explicit application to Gaussian beams and apertured focused fields in the paraxial regime. Finally we discuss how our procedure can be favorably implemented in scattering problems.