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John Adams acquired an unrivalled reputation for his leading part in designing and constructing the Proton Synchrotron (PS) in CERNs early days. In 1968, and after several years heading a fusion laboratory in the UK, he came back to Geneva to pilot the Super Proton Synchrotron (SPS) project to approval and then to direct its construction. By the time of his early death in 1984 he had built the two flagship proton accelerators at CERN and, during the second of his terms as Director-General, he laid the groundwork for the proton-antiproton collider which led to the discovery of the intermediate vector boson. How did someone without any formal academic qualification achieve this? What was the magic behind his leadership? The speaker, who worked many years alongside him, will discuss these questions and speculate on how Sir John Adams might have viewed todays CERN.
John Couch Adams predicted the location of Neptune in the sky, calculated the expectation of the change in the mean motion of the Moon due to the Earths pull, and determined the origin and the orbit of the Leonids meteor shower which had puzzled astronomers for almost a thousand years. With his achievements Adams can be compared with his good friend George Stokes. Not only were they born in the same year, but were also both senior wranglers, received the Smiths Prizes and Copley medals, lived, thought and researched at Pembroke College, and shared an appreciation of Newton. On the other hand, Adams prediction of Neptunes location had absolutely no influence on its discovery in Berlin. His lunar theory did not offer a physical explanation for the Moons motion. The origin of the Leonids was explained by others before him. Adams refused a knighthood and an appointment as Astronomer Royal. He was reluctant and slow to publish, but loved to derive the values of logarithms to 263 decimal places. The maths and calculations at which he so excelled mark one of the high points of celestial mechanics, but are rarely taught nowadays in undergraduate courses. The differences and similarities between Adams and Stokes could not be more striking. This volume attests to the lasting legacy of Stokes scientific work. What is then Adams legacy? In this contribution I will outline Adams life, instances when Stokes and Adams lives touched the most, his scientific achievements and a usually overlooked legacy: female higher education and support of a woman astronomer.
Drive particle beams in linear or weakly nonlinear regimes of the plasma wakefield accelerator quickly reach a radial equilibrium with the wakefield, which is described in detail for the first time. The equilibrium beam state and self-consistent wakefields are obtained by combining analytical relationships, numerical integration, and first-principle simulations. In the equilibrium state, the beam density is strongly peaked near the axis, the beam radius is constant along the beam, and longitudinal variation of the focusing strength is balanced by varying beam emittance. The transverse momentum distribution of beam particles depends on the observation radius and is neither separable, nor Gaussian.
On this, the occasion of the 20th anniversary of the Ising Lectures in Lviv (Ukraine), we give some personal reflections about the famous model that was suggested by Wilhelm Lenz for ferromagnetism in 1920 and solved in one dimension by his PhD student, Ernst Ising, in 1924. That work of Lenz and Ising marked the start of a scientific direction that, over nearly 100 years, delivered extraordinary successes in explaining collective behaviour in a vast variety of systems, both within and beyond the natural sciences. The broadness of the appeal of the Ising model is reflected in the variety of talks presented at the Ising lectures ( http://www.icmp.lviv.ua/ising/ ) over the past two decades but requires that we restrict this report to a small selection of topics. The paper starts with some personal memoirs of Thomas Ising (Ernsts son). We then discuss the history of the model, exact solutions, experimental realisations, and its extension to other fields.
This is a brief account of the legacy of Ken Wilson in statistical physics, high energy physics, computing and education.
This is a historical account from my personal perspective of the development over the last few decades of the standard model of particle physics. The model is based on gauge theories, of which the first was quantum electrodynamics, describing the interactions of electrons with light. This was later incorporated into the electroweak theory, describing electromagnetic and weak nuclear interactions. The standard model also includes quantum chromodynamics, the theory of the strong nuclear interactions. The final capstone of the model was the Higgs particle discovered in 2012 at CERN. But the model is very far from being the last word; there are still many gaps in our understanding.