اشترك بالحزمة الذهبية واحصل على وصول غير محدود شمرا أكاديميا
تسجيل مستخدم جديدSpeeches by V. F. Weisskopf, J. H. Van Vleck, I. I. Rabi, M. Hamermesh, B. T. Feld, R. P. Feynman, and D. Saxon, given in honor of Julian Schwinger at his 60th birthday
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In February 1978 Julian Schwingers 60th birthday was celebrated with a SchwingerFest at UCLA. This article consists of transcripts of historical talks given there.
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In the early 1980s, Schwinger made seminal contributions to the semiclassical theory of atoms. There had, of course, been earlier attempts at improving upon the Thomas--Fermi model of the 1920s. Yet, a consistent derivation of the leading and next-to
-leading corrections to the formula for the total binding energy of neutral atoms, $$-frac{E}{e^2/a_0} = 0.768745Z^{7/3} - frac{1}{2}Z^2+0.269900Z^{5/3} + cdots,,$$ had not been accomplished before Schwinger got interested in the matter; here, $Z$ is the atomic number and $e^2/a_0$ is the Rydberg unit of energy. The corresponding improvements upon the Thomas--Fermi density were next on his agenda with, perhaps, less satisfactory results. Schwingers work not only triggered extensive investigations by mathematicians, who eventually convinced themselves that Schwinger got it right, but also laid the ground, in passing, for later refinements --- some of them very recent.
Boris R. Vainberg was born on March 17, 1938, in Moscow. His father was a Lead Engineer in an aviation design institute. His mother was a homemaker. From early age, Boris was attracted to mathematics and spent much of his time at home and in school w
orking through collections of practice problems for the Moscow Mathematical Olympiad. His first mathematical library consisted of the books he received as one of the prize-winners of these olympiads.
Locally-rotationally-symmetric Bianchi type-I viscous and non -viscous cosmological models are explored in general relativity (GR) and in f(R,T) gravity. Solutions are obtained by assuming that the expansion scalar is proportional to the shear scalar
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We show that the recent reinterpretation of oxygen isotope effects in cuprate superconductors by D. R. Harshman et al. is mathematically and physically incorrect violating the Anderson theorem and the Coulomb law.
An LRS Bianchi-I space-time model is studied with constant Hubble parameter in $f(R,T)=R+2lambda T$ gravity. Although a single (primary) matter source is considered, an additional matter appears due to the coupling between matter and $f(R,T)$ gravity
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