The occupation of the Niels Bohr Institute by German authorities in war-time Denmark has hitherto not been described or analyzed in detail, leaving a number of questions open, such as the background and purpose of the occupation, the lack of planning of the operation, formation, mandate and actual work of the “Expert Commission,” and the justification of release without conditions. These questions

This paper is the first investigation of the events associated with the discovery of the antiproton. The 1955 observation of the antiproton by Owen Chamberlain, Emilio Segrè, Clyde Wiegand, and Thomas Ypsilantis was “no surprise,” in Chamberlain’s words, and might therefore be understood as a classic example of an experimental proof of an existing theory—except there was no complete theory—at best

The introductory physics course taught in American College and Universities in the twenty-first century is a descendent of the natural philosophy—later, physics—course that developed in these institutions in the nineteenth century. In the present paper, I discuss the backgrounds of a number of prominent professors of natural philosophy who taught these courses. These came, variously from experience

This paper explores the mechanical models elaborated by projectile theorists throughout the eighteenth century to explain the reflection of light. Influenced by Isaac Newton’s Opticks, these projectile theorists proposed that repulsion was the cause of reflection. My purpose is to show that their models were not unified and lacked a deeper understanding of the origin of repulsive powers. This analysis

Mindful of a stated Project 2061 goal of the American Association for the Advancement of Science, emphasizing that “scientific literacy includes seeing the scientific endeavor in the light of cultural and intellectual history,” and in the continuing spirit of narrowing the gap between the “two cultures” by enhancing STEAM awareness and education, this essay illustrates, quite literally through well-known

We consider the proposal by many scholars and by the International Astronomical Union to rename Hubble’s law as the Hubble-Lemaître law. We find the renaming questionable on historic, scientific, and philosophical grounds. From a historical perspective, we argue that the renaming presents an anachronistic interpretation of a law originally understood as an empirical relation between two observables

I re-examine the raw data of the measurements of the half-life of 210Po from the Romanian physicist Ştefania Mărăcineanu’s doctoral thesis, performed at the Institut du Radium, 1921–1923, under the supervision of Marie Curie. The half-life values reported in the thesis show relatively large divergences and a possible dependence on the (metallic) support on which the Po source was deposited. These findings

We reconstruct Enrico Fermi’s remarkable discovery of neutron-induced radioactivity in March 1934 with a focus on the experimental apparatus he used, such as the original neutron sources preserved in Italy and abroad. Special attention is paid to the role of the Radium Office of the Institute of Public Health in Rome in providing to Fermi the “radium emanation” (Radon-222) used to make his radon-beryllium

The paper is focused on the two most outstanding figures among the Jesuit missionaries in seventeenth-century China: Johann Adam Schall von Bell and Ferdinand Verbiest. Schall aimed to introduce the telescope into Chinese astronomy, which was traditionally based on naked-eye observation and calculation. With the advent of the Qing dynasty, he became head of the Mathematical Board and director of the

The concept of “fact” has a history. Over the past centuries, physicists have appropriated it in various ways. In this article, we compare Ernst Mach and Albert Einstein’s interpretations of the concept. Mach, like most nineteenth-century German physicists, contrasted fact and theory. He understood facts as real and complex combinations of natural events. Theories, in turn, only served to order and

Western missionaries played an important role as go-betweens, promoting communication and interaction between Europe and China in science, culture, and religion. In 1644, the Qing government appointed the Germany Jesuit missionary Johann Adam Schall von Bell head of the Bureau of Astronomy, placing him in charge of reforming the Chinese calendar. In the traditional calendar, in addition to dates based

The American physicist John Wheeler once told his colleague Richard Feynman that, in case of war, “it’s better to forget physics and tell the admirals and generals how to do tactical and strategic this-and-that.” This article explores the history of this-and-that distinctions between tactical and strategic nuclear weapons in the early Cold War. The idea of tactical nuclear weapons was intertwined with

As the History of Science Society, which is based in America, holds its annual meeting in Utrecht, one of the key academic centers on the European continent, one may surmise that the field has returned home. Yet, this hardly reflects how today’s world of scholarship is constituted: in the historiography of science, “provincializing Europe” has become an important theme, while the field itself, as is

The article ‘Einstein’s Gyros’ written by József Illy was originally published electronically

Einstein’s life-long effort to develop a theory that unifies gravitation and electromagnetism was not a purely theoretical enterprise. The technical environment of a gyrocompass factory triggered his search for a novel connection between the rotation of an electrically uncharged body and its magnetic field. The dimensional equality of the electric unit charge and the mass of a body multiplied by the

The concept of constants of nature originated in the late-nineteenth century and has since then increasingly occupied the minds of physicists. But are the constants truly constant? Inspired by Paul Dirac’s suggestion that the gravitational constant varies slowly in time, the question was addressed not only by physicists but also by astronomers, geologists, and paleontologists. Pascual Jordan in Germany

In the original publication of this article, the author noticed some minor errors.

Recent historiographic results in Galilean studies disclose the use of proportions, graphical representation of the kinematic variables (distance, time, speed), and the medieval double distance rule in Galileo’s reasoning; these have been characterized as Galileo’s “tools for thinking.” We assess the import of these “tools” in Galileo’s reasoning leading to the laws of fall (\(v^{2} \propto D\) and

Karl Przibram is one of the pioneers of early solid state physics in the field of the interdependence of coloration effects and luminescence in solids (crystals, minerals) induced by radiation. In 1921 Przibram discovered the effect of radio-photoluminescence, the light-stimulated phosphorescence in activated crystals induced by gamma rays. In 1926 Przibram was the first to use the term, Farbzentrum

This is the third in a three-part article describing the development of the experimental program at the Thomas Jefferson National Accelerator Facility, from the first dreams of incisive electromagnetic probes into the structure of the nucleus through the era in which equipment was designed and constructed and a program crafted so that the long-desired experiments could begin. These developments unfolded

Against the background of the current drive toward diversity in modern scientific communities, this paper explores how a scientific practice might become more diverse by the inclusion of peripheral members. To demonstrate how peripheral members gain contributory expertise in the sciences in the absence of mentors and a readymade community, I present a case study of the Indian physicist C. V. Raman

Since the late-nineteenth century, scientists have been labeled with disciplinary fields and scientific achievements have been identified largely with heroic individuals. Reward systems such as the highly visible Nobel Prizes have reinforced such a view of science. This paper examines long-term trends in Nobel Physics awards since 1901 and asks whether the awards have registered the increasing specialization

In this paper, we analyze in a quantitative manner the changing position of Physical Review in the global field of physics, compared to other important physics journals, since the beginning of the twentieth century. This approach complements existing intellectual and institutional accounts of Physical Review’s historical evolution and offers a dynamical portrait of the global landscape of physics journals

The famous nuclear physicist Bruno Pontecorvo, who defected to the USSR in 1950, was affiliated to the internationalist network called “Partisans of Peace,” founded in 1949. Later renamed the World Peace Council, it was an organization of pacifist scientists, intellectuals, and artists like Frédéric Joliot-Curie and Pablo Picasso that was similar to the Pugwash movement, but part of the Comintern (later

Lay people have a large appetite for information about scientific and technological issues that affect them, such as self-driving automobiles, gene manipulation, and climate change. However, this information must be clear and accurate if they are to use it to make informed political decisions. In 1994, the Nobel prize–winning physicist Philip W. Anderson used a newspaper essay to convey his concerns

It is well known that, following the emergence of the first evidence for an expanding universe, Albert Einstein banished the cosmological constant term from his cosmology. Indeed, he is reputed to have labelled the term, originally introduced to the field equations of general relativity in 1917 in order to predict a static universe, his “biggest blunder.” However, serious doubts about this reported

This article, the second in a series about the Russian scientist Mikhail Lomonosov (1711–1765), traces his education from his arrival in Moscow in 1731 to study at the Slavic-Greco-Latin Academy, through his admission to the St. Petersburg Academy of Sciences in 1736, to his trip abroad to complete his educational studies from 1736 to 1741. Lomonosov’s story during this time opens a vista on the introduction

Maxwell’s celebrated electromagnetic theory of light dates from 1865. Two years later, without appealing to the ether as a carrier of light waves, the Danish physicist Ludvig Lorenz (1829–1891) independently published another electrical theory of light based on optical equations and the novel idea of retarded potentials. In spite of resting on a very different conceptual foundation, Lorenz’s theory

In Einstein’s later years, from the late 1920s onward, his reputation in the physics community as an innovator had faded as he pursued increasingly unrealistic unified field theories. Yet from the perspective of the press, his image and ideas were still marketable. We will see how his various attempts to craft a unified field theory generated numerous headlines, despite their lack of experimental evidence

The gradual emergence of a science of hydrostatics during the course of the seventeenth century is testament to the fact that a technical concept of pressure that was up to the task was far from obvious. The first published version of a theory of hydrostatics containing the essentials of the modern theory appeared in book 2 of Isaac Newton’s Principia. Newton derived the propositions of hydrostatics

The fiftieth anniversary year of Brookhaven National Laboratory was momentous, but for reasons other than celebrating its scientific accomplishments. Legacy environmental contamination, community unrest, politics, and internal Department of Energy issues dominated the year. It was the early days of perhaps the most turbulent time in the lab’s history. The consequences resulted in significant changes

This is the second in a three-part article describing the development of the Thomas Jefferson National Accelerator Facility’s experimental program, from the first dreams of incisive electromagnetic probes into the structure of the nucleus through the era in which equipment was designed and constructed and a program crafted so that the long-desired experiments could begin. These developments unfolded

In the early 1960s, a PhD student in physics, Costas Papaliolios, designed a simple—and playful—system of Polaroid polarizer filters with a specific goal in mind: explaining the core principles behind Julian Schwinger’s quantum mechanical measurement algebra, developed at Harvard in the late 1940s and based on the Stern-Gerlach experiment confirming the quantization of electron spin. Papaliolios dubbed

The carbon cycle, or Bethe-Weizsäcker cycle, plays an important role in astrophysics as one of the most important energy sources for quiescent and explosive hydrogen burning in stars. This paper presents the intellectual and historical background of the idea of the correlation between stellar energy production and the synthesis of the chemical elements in stars on the example of this cycle. In particular

In 2016 the LIGO-Virgo collaboration announced “the first direct detection of gravitational waves.” This was to distinguish their result from the indirect observation of Russell Hulse, Joel Weisberg, and Joseph Taylor, which used the decrease in the period of a binary pulsar to “establish, with a high degree of confidence the existence of gravitational radiation as predicted by general relativity.”

This article chronicles the most recent history of the Deutsches Elektronen-Synchrotron (DESY) located in Hamburg, Germany, with particular emphasis on how this national laboratory founded for accelerator-based particle physics shifted its research program toward multi-disciplinary photon science. Synchrotron radiation became DESY’s central experimental research program through a series of changes

With the foundation of the Division of Plasma Physics of the American Physical Society in April 1959, plasma physics was presented as the general study of ionized gases. This paper investigates the degree to which plasma physics, during its first decade, established a community of interrelated specialties, one that brought together work in gaseous electronics, astrophysics, controlled thermonuclear

The development of superconducting wire and cable in the late twentieth century enabled high-field magnets and thus much higher beam-collision energies in accelerators. These higher collision energies have allowed experimentalists to probe further into the structure of matter at the most fundamental, subatomic level. The behavior of the early universe, where these high energies prevailed, and its evolution

Electrostatic accelerators have emerged as a major tool in research and industry in the second half of the twentieth century. In particular in low energy nuclear physics they have been essential for addressing a number of critical research questions from nuclear structure to nuclear astrophysics. This article describes this development on the example of a single machine which has been used for nearly

Galileo’s early inquiries on motion and free fall in Pisa (1588–1592) can be regarded as a case study of multiple knowledge transfer at the very basic roots of modern mechanics. The treatise De motu, unpublished until 1890, is an original but unsuccessful attempt to go beyond Aristotelian physics by extending Archimedean hydrostatics to the dynamics of natural motion and reappraising the late-medieval

This paper describes the life and scientific development of Arthur E. Haas, from his early career as young, ambitious Jewish-Austrian scientist at the University of Vienna to his later career in exile at the University of Notre Dame. Haas is known for his early contributions to quantum physics and as the author of several textbooks on topics of modern physics. During the last decade of his life, he

We assess the scientific value of Oppenheimer’s research on black holes in order to explain its neglect by the scientific community, and even by Oppenheimer himself. Looking closely at the scientific culture and conceptual belief system of the 1930s, the present article seeks to supplement the existing literature by enriching the explanations and complicating the guiding questions. We suggest a rereading

E-36, an experiment on small-angle proton-proton scattering, began testing equipment at the National Accelerator Laboratory (NAL) using a newly achieved 100 GeV proton beam on February 12, 1972, marking the beginning of NAL’s experimental program. This experiment, which drew collaborators from NAL, the Joint Institute for Nuclear Research (Dubna, USSR), the University of Rochester (Rochester, New York)

In 1919, A. C. D. Crommelin and C. R. Davidson, British astronomers from the Greenwich Observatory in England, passed by Amazonia on their Brazilian journey aiming to measure the bending of stars' light rays during the total solar eclipse of May 29, 1919, and thereby put the theory of general relativity to the test. In the context of Crommelin’s and Davidson’s visit, we discuss how Amazonia was introduced

This is the first in a three-part article describing the development of the experimental program at the Thomas Jefferson National Accelerator Facility, from the first dreams of incisive electromagnetic probes into the structure of the nucleus through the era in which equipment was designed and constructed and a program crafted so that the long-desired experiments could begin. Part 1, which is presented

The pressures of politics, the desire to be first in innovation, moral convictions, and the potential dangers of error are all factors that have long been at work in the history of science and technology. Every so often, the need to reach a result may require leaving out a few steps here and there. Historians think and argue best through stories, so what follows are several tales, each of which exemplifies

What powered Einstein’s discoveries? Was it asking naïve questions, stubbornly? Was it a mischievous urge to break rules? Was it the destructive power of operational thinking? It was none of these. Rather, Einstein made his discoveries through lengthy, mundane investigations, pursued with tenacity and discipline. We have been led to think otherwise in part through Einstein’s brilliance at recounting

The modern picture of the neutrino as a multiple-mass, highly mixed neutral particle has emerged over forty years of study. Best known of the issues leading to this picture was the apparent loss of neutrinos coming from the sun. This article describes another piece of evidence that supports the picture; the substantial reduction of high-energy muon-type neutrinos observed in nature. For much of the

The author’s mother, Gertrude Scharff-Goldhaber, was a prominent nuclear physicist who had to overcome steep odds to pursue her work. She lived and worked at a time when it was very uncommon for any woman to be a scientist and even more uncommon for a mother of young children. She also faced Nazi persecution and a series of other challenges in growing up in Germany. Drawing on personal conversations

This paper traces the social and cultural dimensions of quantum physics in colonial India where Satyendranath Bose worked. By focusing on Bose’s approach towards the quantum and his collaboration with Albert Einstein, I argue that his physics displayed both the localities of doing science in early twentieth century India as well as a cosmopolitan dimension. He transformed the fundamental new concept

Anyone who studies the history of physics quickly realizes that the history presented in physics textbooks is often inaccurate. I will discuss three episodes from the history of modern physics: (1) Robert Millikan’s experiments on the photoelectric effect, (2) the Michelson-Morley experiment, and (3) the Ellis-Wooster experiment on the energy spectrum in β decay. Everyone knows that Millikan’s work

The focus of this broad historical overview of “the steady evolution of theoretical ideas” from Shelter Island I in 1947 to Shelter Island II in 1983 is some of the developments in “fundamental” physics after the establishment of the standard model, in particular, the adoption of the view that all present day field theories are “effective field theories” based on the gauge concept; taking seriously

To save China from the perils she faced in the early twentieth century, the majority of the Chinese seemed to agree that it was necessary to strengthen the country by developing shiye or industry and commerce. For this purpose, they overhauled China’s education system and sent a large number of students to study overseas. Many of them enrolled in American colleges, sponsored either by governmental