May 20th, 2020

квадратная птица Владислав

Аполлон-11 и фундаментальная наука

Apollo 11 and Fundamental Science:
A. De Rújula
Half a century after a man first set foot on the moon it is interesting to revisit the occasion with a measure of hindsight. From the point of view of basic science the greatest achievement concerned the implementation of the Nordtvedt test, a precise check of Einstein's strong equivalence principle. A particle physicist may bravely interpret the result as a precise measurement of the triple-graviton coupling. Other not so profound experiments were also (unofficially) made in Apollo flights, such as a long-distance test of ESP (yes! extra sensory perception). From a sociopolitical point of view the lesson concerns the feats that can be achieved by a determined and united country... or more than one.
Comments: 12 pages, 5 figures. Extended version of an article published in Inference
лошадь, диаграмма, Фейнман

Что-то симпатичное по механике

Planar motion with Fresnel integrals as components of the velocity:

E. Flores-Garduno, S.C. Mancas, H.C. Rosu, M. Perez-Maldonado
We analyze the two-dimensional motion of a rigid body due to a constant torque generated by a force acting on the body parallel to the surface on which the body moves extending an old note of Ferris-Prabhu [Am. J. Phys 38, 1356-1357 (1970)]
Comments: 5 pages, 2 figures