July 27th, 2021

лошадь, диаграмма, Фейнман

Вывод распределения Максвелла на португальском

Авторы утверждают, что в стандартных курсах приводится только ответ. Что, правда???

The Maxwell-Boltzmann Velocity Distribution Function in Detail: https://arxiv.org/abs/2107.12354
Gilberto Jonas Damião, Clóves Gonçalves Rodrigues
Despite its importance, in the introductory disciplines of exact science courses, the demonstration of the Maxwell-Boltzmann velocity distribution law is not explained, only its final equation is shown. In order to fill this deficiency, in this work we try to show in detail, in a very didactic way, the demonstration of such a law. For this, the kinetic theory of gases is initially introduced. The good agreement of the Maxwell-Boltzmann velocity distribution law with experimental results and its applicability limit is also presented.
Comments: in Portuguese
лошадь, диаграмма, Фейнман

Как выглядит тень от резерфордовского рассеяния в разных системах отсчета

A shadow of the repulsive Rutherford scattering in the laboratory frame: https://arxiv.org/abs/2107.10951
Petar Žugec, Dario Rudec
The paper explores the Rutherford scattering shadow in an entire class of comoving frames -- inertial frames moving along the initial projectile direction -- of which the laboratory frame, where the target is initially at rest, is a representative example. The paper is a continuation of the previous work addressing the scattering shadow in the fixed-target and the center-of-mass frame. It is shown that the transition from these frames is technically quite involved, due to the scattering shadow forming at an infinite distance from an initial target position. The central procedure involves solving the 5th degree polynomial as a part of an associated extremization procedure. The shadow existence itself is subject to certain conditions, dependent on a given comoving frame. A new and unexpected phenomenon is found within a certain set of comoving frames, including the laboratory frame itself. It consists of a phase transition between an entirely smooth type of shadow and the one characterized by a formation of a sharp edge.
Comments: 25 pages, 19 figures