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تسجيل مستخدم جديدPhoton-photon scattering and related phenomena. Experimental and theoretical approaches: The early period
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K. Scharnhorst
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We review the literature on possible violations of the superposition principle for electromagnetic fields in vacuum from the earliest studies until the emergence of renormalized QED at the end of the 1940s. The exposition covers experimental work on photon-photon scattering and the propagation of light in external electromagnetic fields and relevant theoretical work on nonlinear electrodynamic theories (Born-Infeld theory and QED) until the year 1949. To enrich the picture, pieces of reminiscences from a number of (theoretical) physicists on their work in this field are collected and included or appended.
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Photon-induced reactions play a key role in the nucleosynthesis of rare neutron-deficient p-nuclei. The paper focuses on (gamma,alpha), (gamma,p), and (gamma,n) reactions which define the corresponding p-process path. The relation between stellar rea
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The first time one of us (G.P.) encountered Earle was in Summer 1966, when she was directed to study Earles papers on radiative corrections to quasi-elastic electron scattering. The suggestion had come from Bruno Touschek, at the time head of the the
oretical physics group at the Frascati National Laboratories near Rome. About the same time, Earle came from MIT to visit University of Rome and Frascati. G.P. was a young post-graduate, who had studied Earles papers and was awed by his already impressive scientific figure. After almost 40 years had passed, Earle visited Italy with his wife Ruth, making Frascati their base for an extended visit of almost a month. They were housed in what was then the laboratory hostel for foreign visitors, a small villa higher up above the hill, toward the town of Frascati. Since then, we became close friends, a friendship which included both his family and ours, and which has been very important for us. In memory of that first visit and in gratitude for the many years of friendship, we will tell here a story of infrared radiative corrections to charged particle scattering, to which Earles papers gave an important contribution.
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