Results 1 - 10 of 1200
Results 1 - 10 of 1200. Search took: 0.022 seconds
|Sort by: date | relevance|
[en] The matrix elements of a single-particle Hamiltonian were constructed from a folding Gaussian type of potential defined by a domain limited by a sphere R(N)=r0Asup(1/3) with conventional absorption terms. A method of computable R matrix giving S phase shifts was developed
[fr]Partant d'un potentiel du type ''folding gaussien'' defini par un domaine D limite par une sphere de rayon R(N)=r0Asup(1/3) auquel on adjoint les termes d'absorption habituels on a construit les elements de matrice du hamiltonien a 1 particule. On a mis au point une methode de matrice R calculable fournissant les dephasages
[en] Measurement-induced nonlocality is a measure of nonlocality introduced recently by Luo and Fu. We present here sufficient and necessary conditions for a quantum state for which this quantity is equal to zero. Furthermore it is shown that for such a state ρab with dim Ha = d ≥ 3 any local channel acting on Ha cannot create measurement-induced nonlocality if and only if either it is a completely contractive channel or it is a nontrivial isotropic channel. For the qubit case this property is an additional characteristic of the completely contractive channel or the commutativity-preserving unital channel. (paper)
[en] The probability of pair creation by a separable and nonlocal potential is considered following the Schwinger approach. It has been found that this probability is null. As a particular case, the separable δ potential is considered, and the probability is also found null.
[en] Two methods to change a quantum harmonic oscillator frequency without transitions in a finite time are described and compared. The first method, a transitionless-tracking algorithm, makes use of a generalized harmonic oscillator and a non-local potential. The second method, based on engineering an invariant of motion, only modifies the harmonic frequency in time, keeping the potential local at all times.
[en] The notion of “weak classical limit” for coupled N-level quantum systems as N → ∞ is introduced to understand the precise sense in which one attains classicality. There exists proofs that a system becomes classical at large N [1, 2]. On the other hand, it is known that non-locality and entanglement, the two hallmarks of non-classicality, thrive even as N → ∞. We reconcile these results in this paper by showing that so called classicality is not so much an inherent property of the system, as it is a consequence of limited experimental resources. Our focus is largely on non-locality, for which we study the Bell-CHSH and CGLMP inequalities for N-level systems. Graphical abstract: .
[en] A computer calculation was developed for bound states using the nonlocal potential (Perey-Buck potential). The parameters of the folding model fitted on Hartree-Fock-Bogolyubov results are given for 208Pb
[fr]Un calcul des etats lies dans le potentiel non-local (Perey-Buck) a ete programme. On donne les parametres du modele de convolution ajustes sur les resultats Hartree-Fock-Bogolyubov de 208Pb
[en] Equations of fractal motion of electrons with variable weak memory and nonlocality are investigated. It is demonstrated that the fractal dimension of time changes according to harmonic law for stationary electron motion. The fractal nonlocality has been established for the free electron; it also changes according to the harmonic law. The fractal nonlocality of the electron bound with the hydrogen atom nucleus differs radically. In this case, the fractal dimension of radial electron motion is even less than unity. It can be greater than unity in regions well away from the nucleus
[ru]Исследуются уравнения фрактального движения электрона с переменной слабой паматью и нелокальностью. Показано, что при стационарном движении электрона размерность фрактального времени меняется по гармоническому закону. Для свободного электрона обнаружена фрактальная нелокальность, также меняющаяся по гармоническому закону. Принципиально иной характер фрактальной нелокальности испытывает электрон, связанный с ядром атома водорода. Фрактальная размерность радиальных движений этого электрона всюду меньше единицы. При особых условиях она может быть и больше единицы в области, достаточно удаленной от ядра
[en] It is revealed that ensembles consisting of multipartite quantum states can exhibit different kinds of nonlocalities. An operational measure is introduced to quantify nonlocalities in ensembles consisting of bipartite quantum states. Various upper and lower bounds for the measure are estimated and the exact values for ensembles consisting of mutually orthogonal maximally entangled bipartite states are evaluated.