Fritz Reiche and the Emergency Committee in Aid of Displaced Foreign Scholars

I discuss the family background and early life of the German theoretical physicist Fritz Reiche (1883–1969) in Berlin; his higher education at the University of Berlin under Max Planck (1858–1947); his subsequent work at the University of Breslau with Otto Lummer (1860–1925); his return to Berlin in 1911, where he completed his Habilitation thesis in 1913, married Bertha Ochs the following year, became a friend of Albert Einstein (1879–1955), and worked during and immediately after the Great War. In 1921 he was appointed as ordentlicher Professor of Theoretical Physics at the University of Breslau and worked there until he was dismissed in 1933. He spent the academic year 1934–1935 as a visiting professor at the German University in Prague and then returned to Berlin, where he remained until, with the crucial help of his friend Rudolf Ladenburg (1882–1952) and vital assistance of the Emergency Committee in Aid of Displaced Foreign Scholars, he, his wife Bertha, and their daughter Eve were able to emigrate to the United States in 1941 (their son Hans had already emigrated to England in 1939).From 1941–1946 he held appointments at the New School for Social Research in New York, the City College of New York, and Union College in Schenectady, New York, and then was appointed as an Adjunct Professor of Physics at New York University, where his contract was renewed year-by-year until his retirement in 1958.     

Paul Ehrenfest, Niels Bohr, and Albert Einstein: Colleagues and Friends

In May 1918 Paul Ehrenfest received a monograph from Niels Bohr in which Bohr had used Ehrenfest’s adiabatic principle as an essential assumption for understanding atomic structure. Ehrenfest responded by inviting Bohr, whom he had never met, to give a talk at a meeting in Leiden in late April 1919, which Bohr accepted; he lived with Ehrenfest, his mathematician wife Tatyana, and their young family for two weeks. Albert Einstein was unable to attend this meeting, but in October 1919 he visited his old friend Ehrenfest and his family in Leiden, where Ehrenfest told him how much he had enjoyed and profited from Bohr’s visit. Einstein first met Bohr when Bohr gave a lecture in Berlin at the end of April 1920, and the two immediately proclaimed unbounded admiration for each other as physicists and as human beings. Ehrenfest hoped that he and they would meet at the Third Solvay Conference in Brussels in early April 1921, but his hope was unfulfilled. Einstein, the only physicist from Germany who was invited to it in this bitter postwar atmosphere, decided instead to accompany Chaim Weizmann on a trip to the United States to help raise money for the new Hebrew University in Jerusalem. Bohr became so overworked with the planning and construction of his new Institute for Theoretical Physics in Copenhagen that he could only draft the first part of his Solvay report and ask Ehrenfest to present it, which Ehrenfest agreed to do following the presentation of his own report. After recovering his strength, Bohr invited Ehrenfest to give a lecture in Copenhagen that fall, and Ehrenfest, battling his deep-seated self-doubts, spent three weeks in Copenhagen in December 1921 accompanied by his daughter Tanya and her future husband, the two Ehrenfests staying with the Bohrs in their apartment in Bohr’s new Institute for Theoretical Physics. Immediately after leaving Copenhagen, Ehrenfest wrote to Einstein, telling him once again that Bohr was a prodigious physicist, and again expressing the hope that he soon would see both of them in Leiden.     

The Disappearance and Death of Ettore Majorana

At the end of March 1938, Ettore Majorana disappeared under still mysterious circumstances while he was Professor of Theoretical Physics at the University of Naples. We exploit new archival documents that provide evidence that without any doubt he was deceased before September 1939. These include documents pertaining to the foundation of a Fellowship in his name, announced on November 3, 1939, in the journal, The Missions of the Society of Jesus, and documents pertaining to the Police and Vatican inquires after his disappearance. We conclude by discussing the biographical sketch of Majorana that his uncle Giuseppe Majorana wrote before his death in 1940.     

Heike Kamerlingh Onnes and the Nobel Prize in Physics for 1913: The Highest Honor for the Lowest Temperatures

One century ago this year the Dutch experimental physicist Heike Kamerlingh Onnes (1853–1926) was awarded the Nobel Prize in Physics for his work in low-temperature physics, in particular for his production of liquid helium. I trace the route to his Nobel Prize within the context of his and his colleagues’ research in his laboratory at the University of Leiden, and in light of his nominators and the nominations he received in the five years 1909–1913.     

In Appreciation Julian Schwinger: From Nuclear Physics and Quantum Electrodynamics to Source Theory and Beyond

Julian Schwinger’s influence on twentieth-century science is profound and pervasive. He is most famous for his renormalization theory of quantum electrodynamics, for which he shared the Nobel Prize in Physics for 1965 with Richard Feynman and Sin-itiro Tomonaga. This triumph undoubtedly was his most heroic work, but his legacy lives on chiefly through subtle and elegant work in classical electrodynamics, quantum variational principles, proper-time methods, quantum anomalies, dynamical mass generation, partial symmetry, and much more. Starting as just a boy, he rapidly became one of the preeminent nuclear physicists in the world in the late 1930s, led the theoretical development of radar technology at the Massachusetts Institute of Technology during World War II, and soon after the war conquered quantum electrodynamics, becoming the leading quantum-field theorist for two decades, before taking a more iconoclastic route during the last quarter century of his life.     

海森伯与中国物理学界

著名物理学家海森伯曾于1929年访华,旋即被聘为中央研究院物理所名誉研究员,成为中国近代物理学史上第一个获此荣誉的外籍学者.文章对他来华的具体时间作出推断,述及其与早期中国物理学界某些人士的因缘.     

Heike Kamerlingh Onnes: Master of Experimental Technique and Quantitative Research

Heike Kamerlingh Onnes (1853-1926), born a century and a half ago, was a major protagonist in the so-called Second Golden Age of Dutch Science. He devoted his career to the emerging field of low-temperature physics. His particular concern was to test the theories of his older compatriot Johannes Diderik van der Waals (1837-1923) by creating a style of research that was characterized by meticulous planning, precise measurement, and constant improvement of techniques and instruments. He made numerous contributions to low-temperature physics, but I focus on his liquefaction of helium, for which he received the Nobel Prize in Physics for 1913, and on his discovery of superconductivity. He became known internationally as le gentleman du zéro absolu.     

Richard Gans: The First Quantum Physicist in Latin America

Richard Gans (1880–1954) was appointed Professor of Physics and Director of the Institute of Physics of the National University of La Plata,Argentina, in 1912 and published a series of papers on quantum physics between 1915 and 1918 that marked him as the first quantum physicist in Latin America. I set Gans’s work within the context of his education and career in Germany prior to 1912 and his life and work in Argentina until 1925, as well as the foundation of the Institute of Physics of the National University of La Plata in 1906–1909 and its subsequent development by Emil Bose (1874–1911). I conclude by commenting on Gans’s life after he returned to Germany in 1925 and then immigrated once again to Argentina in 1947.     

温度效应对F-P腔光纤液位传感器系统的影响及自补偿

分析了温度效应对F-P腔光纤液位传感器系统的影响,提出相应的解决方案以实现对温度效应的自补偿.在26℃-28℃环境温度条件下,实验结果表明,在1.87 m（水）量程内经过优化的传感系统参考光动态稳定性可达到0.059 9%,准确度误差为1.122 mm.自补偿措施对获得高准确度、长期稳定性的光纤液位传感器具有重要意义.     

A Conversation with Lee Alvin DuBridge – Part I

Physicist Lee A. DuBridge became president of the California Institute of Technology in 1946. In this interview he recalls the immediate problems he faced, including his dealings with Robert A. Millikan, whom he replaced as chief administrator of the institute; institute financing and inadequate salaries. DuBridge also talks about the advent of federal support for peacetime science and Millikan's distaste for it; his close working relationship with Robert F. Bacher, who came to the institute in 1949 as chairman of the Division of Physics, Mathematics, and Astronomy; his recollections of the meteorologist Irving P. Krick, the physicist Alexander Goetz, and the chemist Linus Pauling; and his attempts to build up the Humanities Division.     

Laser annealing and theory of photostimulated structures

It is shown that a circularly polarized laser light passing through a disordered system represented by a thin film of an amorphous semiconductor gives rise to a self-organization of new ordered states. Laser annealing of implanted semiconductors, emergence of charge density waves, light-induced transmittance oscillations and optical stopping effect are explained on a unified ground within the framework of quantum field theory.Dedicated to Professor Ivan Úlehla on the occasion of his sixtieth birthday.The authors thank Dr. E. Majerníková for fruitful conversations. One of us (M. Noga) wishes to express his sincere indebtness and gratidude to Prof. Stig Stenholm and Christopher Cronström for valuable discussions at Research Institute for Theoretical Physics, University of Helsinki, where he was given the oportunity to start the research of these problems.     

The BEH mechanism and its scalar boson

The theoretical discovery of a mechanism that contributes to our understanding of the origin of mass of subatomic particles was recently confirmed through the discovery of the predicted fundamental particle, by the ATLAS and CMS experiments at CERN's Large Hadron Collider. In his Nobel lecture, F. Englert gives an overview of this research which has led to the Nobel Prize in Physics in 2013 which he shared with Peter W. Higgs. 1     

Concepts of Time in Physics: A Synopsis

I summarize the historical development of concepts of time in physics from antiquity to the end of the twentieth century. Editors’ Note: Max Jammer received the American Physical Society/American Institute of Physics Abraham Pais Prize for the History of Physics for 2007, “For his groundbreaking historical studies of fundamental concepts in physics, including his comprehensive account of the development of quantum mechanics.” We publish here his Pais Prize Lecture, which was presented at the APS meeting in Jacksonville, Florida, on April 16, 2007.     

Ettore Majorana’s Forgotten Publication on the Thomas-Fermi Model

We analyze the forgotten communication of Ettore Majorana (1906–1938?) on the Thomas-Fermi statistical model of the atom, which he presented on December 29, 1928, during the XXII General Meeting of the Italian Physical Society in Rome, and which was published in Il Nuovo Cimento, the Society’s journal, in 1929. His communication was not mentioned subsequently in any of the numerous publications of Enrico Fermi (1901–1954) and his group in Rome, nor in any of the later accounts of Majorana’s life and work. We place Majorana’s contribution within the context of contemporary research on the subject, point out its influence on the final formulation of the Thomas-Fermi statistical model by Fermi and Edoardo Amaldi (1908–1989) in 1934, and discuss Majorana’s other scientific contributions before his mysterious disappearance in 1938. Francesco Guerra is Professor of Theoretical Physics in the Department of Physics at the University of Rome “La Sapienza.” His main fields of research are quantum-field theory, statistical mechanics of complex systems, and the history of nuclear physics. Nadia Robotti is Professor of History of Physics in the Department of Physics at the University of Genoa. Her main fields of research are the history of atomic physics, quantum mechanics, and nuclear physics.     

Harry Lehmann

   Harry Lehmann was born in 1924 at Güstrow, Mecklenburg. After graduation from school in Rostock, the German army drafted him in 1942 for service in North Africa, where he was taken prisoner of war by the American forces. He spent three years in a prison camp in the United States; there he had the opportunity to study on his own, and to prepare for the university. When he was released in 1946, he soon returned to his parents in Rostock and began to study physics, first at the University of Rostock, then at the Humboldt University in East Berlin, obtaining his diploma with a thesis on experimental physics. In 1949 he became assistant of Friedrich Hund at the University of Jena, where he wrote his doctoral dissertation on classical electrodynamics. When Hund moved to the University of Frankfurt, Lehmann served at Jena as acting professor, until Hund was replaced. In the fall of 1952, Heisenberg offered Lehmann a position at the Max Planck Institute for Physics in G?ttingen. There he joined an active group of young theorists from Germany and abroad who had come to collaborate with Heisenberg. After his initial stay, he requested permission to extend his visit; but the authorities of the former German Democratic Republic never responded, and so Harry Lehmann remained in the west. As a result it was not until 1976 that he could once again visit his parents in Rostock. A main topic of discussion in Heisenberg's institute was the method of renormalization, that had been developed in the United States and Japan right after the war. This technique made it possible to compute measurable quantities of quantum electrodynamics, and to compare them with experiments, even though divergent integrals entered intermediate stages of the calculations. Despite the enormous success of renormalization theory, made evident by the high-precision agreement between theory and experiment, many physicists of the older generation in Europe remained skeptical and were convinced that the infinities indicated a serious deficiency of quantum field theory. Dirac, for instance, called renormalization theory “a sin against theoretical physics”. On the other hand the younger theoretical physicists were quite enthusiastic. They considered it a challenge to reformulate the theory in such a way that renormalization infinities never occur, either in the formulation of the principles, or in the calculation of observable quantities. Harry Lehmann's publication on the properties of propagators [1] was an early decisive step in this direction. From minimal assumptions he derived the main properties of propagators, and expressed the constants of renormalization by integrals over finite quantities, even though those quantities diverged in perturbation theory. He carried out a large part of his pioneering work in the 1950's, in collaboration with Kurt Symanzik and Wolfhart Zimmermann. The shorthand designation LSZ is familiar to all elementary particle physicists up to this day. The LSZ-formalism and the Lehmann representation are among the most important basic tools of the theory of elementary particles [2]. An important application of this technique in scattering theory provides the relation between scattering amplitudes and time ordered correlation functions. These were derived as an immediate consequence of the asymptotic behavior of field operators in the distant past and future. In 1955 Harry Lehmann left Heisenberg's institute to visit Copenhagen as a member of the CERN Study Group, and in 1956 he accepted a professorship at the University of Hamburg to become the successor to Wilhelm Lenz. He founded the theoretical elementary particle physics group, and for thirty years, his strong personality determined the character of the II. Institut für Theoretische Physik at Hamburg University. He became Professor Emeritus in 1986. He also advised the German Electron Synchrotron laboratory DESY and helped start its theory group by persuading Kurt Symanzik to return there from New York. Many young scientists were strongly influenced by his personality, by his style of discussion in seminars, by the conciseness of his insightful contributions to research, and by his views on physics in general. Harry Lehmann's interest in the theory of dispersion relations led to the beginning of his close collaboration with Res Jost. In the case of equal mass scattering Jost and Lehmann found a representation for matrix elements of the commutator of two field operators between energy-momentum eigenstates [3]. This representation was extended by Dyson to the general case of unequal masses [4]. On the basis of the Dyson representation, Lehmann derived dispersion relations and other analytic properties of the scattering amplitudes as a consequence of locality, relativistic invariance and conditions on the particle spectrum [5]. These results are also valid for composite particles despite their internal structure, since only general properties are used in the derivation which are independent of the dynamics of the system. Dispersion relations, therefore, provide an experimental test for the principles of local quantum field theory. Harry Lehmann remained active in research until the end of his life. He directed several NATO Advanced Study Institutes in Cargèse (France). With K. Pohlmeyer he worked on field theories with non-polynomial Lagrangians. During his last years he investigated symmetry breaking effects for the quark mass spectrum together with T. T. Wu. Harry Lehmann's scientific merits were recognized in many ways. He received the Max Planck medal of the German Physical Society 1967 and he was made a Chevalier de la Legion d'Honneur on December 31, 1969. He was honoured in 1997 by the Dannie Heineman Prize of the American Physical Society and the American Institute of Physics. Harry Lehmann was an excellent speaker with the remarkable ability to communicate involved and difficult subjects understandably. We remember him gratefully, in friendship, and with esteem for his scientific work.     

Paul Ehrenfest’s Rough Road to Leiden: A Physicist’s Search for a Position, 1904–1912

Paul Ehrenfest (1880–1933) received his Ph.D. degree at the University of Vienna in 1904 and moved with his wife and young daughter to St. Petersburg in 1907, where he remained until he succeeded Hendrik Antoon Lorentz (1853–1928) in the chair of theoretical physics at the University of Leiden in 1912. Drawing upon Ehrenfest’s correspondence of the period, we first examine Ehrenfest’s difficult and insecure years in St. Petersburg and then discuss his unsuccessful attempts to obtain a position elsewhere before he was appointed as Lorentz’s successor in Leiden. Pim Huijnen is writing a doctoral dissertation in history; the present paper is based upon his Master’s Thesis, “‘Die Grenze des Pathologischen’: Het leven van fysicus Paul Ehrenfest, 1904–1912,” University of Groningen, 2003. A.J.Kox is Pieter Zeeman Professor of History of Physics at the University of Amsterdam.     

Quirino Majorana’s Experiments on the Speed of Light and Gravitational Absorption

Quirino Majorana (1871–1957) was an outstanding Italian experimental physicist who investigated a wide range of phenomena during his long career in Rome,Turin, and Bologna. We focus on his experiments in Turin during 1916–1921 and in Bologna during 1921–1934 to test the validity of Albert Einstein’s postulate on the constancy of the speed of light and to detect gravitational absorption. These experiments required extraordinary skill, patience, and dedication, and all of them confirmed Einstein’s postulate and Isaac Newton’s law of universal gravitation to high precision. Had they not done so, Majorana’s fame among historians and physicists no doubt would be much greater than it is today. Giorgio Dragoni is Professor of History of Physics at the University of Bologna. Giulio Maltese is a Roman member of the Italian Society for the History of Physics and Astronomy. Luisa Atti is a Bolognese member of the Association for the Teaching of Physics.     

Henri Victor Regnault: Experimentalist of the Science of Heat

Henri Victor Regnault (1810–1878) was one of the most famous French experimental scientists of the nineteenth century. After studying and carrying out research at the école Polytechnique and the école des Mines in Paris, he was elected to the Paris Académie des Sciences in 1840 and was appointed Professor of Experimental Physics at the Collège de France in 1841. His initial researches were in chemistry, but his careful experimental investigations of the law of the specific heat of solids that Pierre Louis Dulong (1785–1838) and Alexis Thérèse Petit (1791–1820) proposed in 1818 opened the door to his transition to physics and to his pioneering experimental researches on various thermodynamic properties of liquids and gases. I focus particularly on his investigations on the expansion, compressibility, vapor pressure, and speed of sound in gases. He also made important contributions to the new art of photography and to the ceramic industry as director of the Sèvres factory, at a time when his personal life was filled with tragedy. While his experimental work was acclaimed by his contemporaries, it has been largely neglected by scientists and historians today.     

Analogy between the Magnetic Dipole Moment at the Surface of a Magnetoelectric and the Electric Charge at the Surface of a Ferroelectric

Journal of Experimental and Theoretical Physics - In honor of Igor Dzyaloshinskii on his 90th birthday, we revisit his pioneering work on the linear magnetoelectric effect in light of the modern...     

Essay: Samuel Abraham Goudsmit (1902-1978)

When Sam Goudsmit was 23, he and George Uhlenbeck hypothesized that the electron had spin. Sam was a well-known atomic physicist working at the University of Michigan when World War II began. During the war he first worked on radar at the MIT Radiation Lab, and then in the waning days of the war in Europe he led a mission to determine how far the Nazis had gotten in developing an atomic bomb. After chairing the Physics Department at Brookhaven, in 1950 APS named Goudsmit Managing Editor of Physical Review and Reviews of Modern Physics; in 1966 he was named Editor-in-Chief. He founded Physical Review Letters in 1958.