About soft photon resummation

The first time one of us (G.P.) encountered Earle was in Summer 1966, when she was directed to study Earle's papers on radiative corrections to quasi-elastic electron scattering [1, 2]. The suggestion had come from Bruno Touschek [ 3], at the time head of the theoretical 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 Earle's 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 Earle's papers gave an important contribution

Introduction to the physics of the total cross-section at LHC: a Review of Data and Models

This review describes the development of the physics of hadronic cross sections up to recent LHC results and cosmic ray experiments. We present here a comprehensive review - written with a historical perspective - about total cross-sections from medium to the highest energies explored experimentally and studied through a variety of methods and theoretical models for over sixty years. We begin by recalling the analytic properties of the elastic amplitude and the theorems about the asymptotic behavior of the total cross-section. A discussion of how proton-proton cross-sections are extracted from cosmic rays at higher than accelerator energies and help the study of these asymptotic limits, is presented. This is followed by a description of the advent of particle colliders, through which high energies and unmatched experimental precisions have been attained. Thus the measured hadronic elastic and total cross-sections have become crucial instruments to probe the so called soft part of QCD physics, where quarks and gluons are confined, and have led to test and refine Regge behavior and a number of difiractive models. As the c.m. energy increases, the total cross-section also probes the transition into hard scattering describable with perturbative QCD, the so-called mini-jet region. Further tests are provided by cross-section measurements of γp, γ*p and γ*γ* for models based on vector meson dominance, scaling limits of virtual photons at high Q2 and the BFKL formalism. Models interpolating from virtual to real photons are also tested. It seems to us to be a necessary task to explore bit-by-bit the rigorous consequences of analyticity, unitarity and crossing. Who knows if someday one will not be able to reassemble the pieces of the puzzle. - A.Martin and F. Cheung, based on 1967 A.M. Lectures at Brandeis Summer School and Lectures at SUNYand Stony Brook

Charged lepton and neutrino oscillations

Problems long present in the conventional formalism employed for neutrino oscillations are discussed. We here develop a more satisfactory framework based on the Dirac equation and its propagators. When 4-momentum conservation is strictly enforced, there will be induced oscillations in space (but not between generations) for the charged leptons, e.g. $\mu$ and $\tau$ , produced in association with the neutrinos. The oscillations are computed explicitly for the pion decay $\pi \to \mu+\bar{\nu}$ . Leptonic decays of the $W$ are also briefly discussed

Viscosity of High Energy Nuclear Fluids

Relativistic high energy heavy ion collision cross sections have been interpreted in terms of almost ideal liquid droplets of nuclear matter. The experimental low viscosity of these nuclear fluids have been of considerable recent quantum chromodynamic interest. The viscosity is here discussed in terms of the string fragmentation models wherein the temperature dependence of the nuclear fluid viscosity obeys the Vogel-Fulcher-Tammann law.Comment: 6 pages, ReVTeX 4 format, two figures, *.eps forma

QCD predictions for total cross-sections and the Froissart Bound

This article does not have an abstract

Non-chemical signatures of biological materials: Radio signals from Covid19?

All therapeutic methods dealing with coronavirus (past and present) are based on chemicals. We test for it (positive or negative) chemically and hope to cure it with a future vaccine (some complicated chemical preparation). If and when the virus mutates, another set of chemical protocols for its testing and a hunt for new chemicals as a vaccine shall begin again and again. But the history of modern (western) medicine tells us that our biotechnology is not so limited. Copious scientific evidence for sonic and low energy electromagnetic signals produced by all biological elements (DNA, cells, bacteria, parasites, virus) exists; in turn, the biological elements are affected by these non-chemical signals as well. A careful analysis and a catalogue of the spectrum of these non-chemical signals are proposed here as a unique biophysical signature