The story of superheavy elements - those at the very end of the periodic table - is not well known outside the community of heavy-ion physicists and nuclear chemists. But it is a most interesting story which deserves to be known also to historians, philosophers, and sociologists of science and indeed to the general public. This is what the present work aims at. It tells the story or rather parts of the story, of how physicists and chemists created elements heavier (...) than uranium or searched for them in nature. And it does so with an emphasis on the frequent discovery and naming disputes concerning the synthesis of very heavy elements. Moreover, it calls attention to the criteria which scientists have adopted for what it means to have discovered a new element. In this branch of modern science it may be more appropriate to speak of creation instead of discovery. The work will be of interest to scientists as well as to scholars studying modern science from a meta-perspective. (shrink)

In 1876 the Italian physicist and physical chemist Adolfo Bartoli discussed a thought experiment in which he connected the second law of thermodynamics with the hypothetical pressure of radiation. Bartoli's work, published in Italian, exerted some influence on the subsequent development of black-body theory and light pressure research. This influence was mainly due to Boltzmann, who came to the Stefan-Boltzmann radiation law via a reworking of Bartoli's thought experiment. However, contrary to what is usually assumed, Bartoli was himself reluctant to (...) admit the existence of light pressure and soon rejected the hypothesis. Bartoli's work is discussed and related to other work in the areas of radiometer research and thermodynamics. (shrink)

While Karl Popper’s philosophy of science has only few followers among modern philosophers, it is easily the view of science with the biggest impact on practicing scientists. According to Peter Medawar, Nobel laureate and eminent physiologist, Popper was the greatest authority ever on the scientific method. He praised the “great strength of Karl Popper’s conception of the scientific process,” a main reason for the praise being “that it is realistic—it gives a pretty fair picture of what goes on in real (...) life laboratories” (Medawar 1990, p. 100). Either explicitly or (more often) implicitly, many scientists subscribe to some version of simplified Popperianism, usually by adopting the demarcation criterion that a .. (shrink)

Summary Cosmology has always been different from other areas of the natural sciences. Although an observationally supported standard model of the universe emerged in the 1960s, more speculative models and conceptions continued to attract attention. During the last decade, ideas of multiple universes (the ‘multiverse’) based on anthropic reasoning have become very popular among cosmologists and theoretical physicists. This had led to a major debate within the scientific community of the epistemic standards of modern cosmology. Is the multiverse a scientific (...) hypothesis, or is it rather a philosophical speculation disguised as science? This paper offers a review of the recent and still ongoing controversy concerning the multiverse, emphasizing its foundational nature and relation to philosophical issues. It also compares the multiverse controversy to some earlier episodes in the history of twentieth-century cosmology when particular theories and approaches came under attack for betraying the ideals of proper science. (shrink)

This book presents the history of how the universe at large became the object of scientific understanding. Starting with the ancient creation myths, it offers an integrated and comprehensive account of cosmology that covers all major events from Aristotle's Earth-centred cosmos to the recent discovery of the accelearting universe.

No other scientist may have had a greater impact on modern cosmology than the Belgian physicist, astronomer and priest Georges Lemaître. In 1927 he predicted the expansion of the universe on the basis of the cosmological field equations; and four years later he proposed what he called the primeval-atom hypothesis, the first version of the later big bang universe. In all his work on cosmology the cosmological constant Λ played a significant role. A recognized expert in the theory of general (...) relativity, Lemaître also contributed significantly to the theoretical clarification of local and global singularity problems. Still, when he died in 1968, at a time when the standard big bang model celebrated its first victories, he was largely forgotten or recalled only as a somewhat shadowy figure of the past. This essay reviews in a historical context the scientific work of Lemaître with particular attention to his seminal contributions in the decade between 1925 and 1934. (shrink)

During the last decade new developments in theoretical and speculative cosmology have reopened the old discussion of cosmology's scientific status and the more general question of the demarcation between science and non-science. The multiverse hypothesis, in particular, is central to this discussion and controversial because it seems to disagree with methodological and epistemic standards traditionally accepted in the physical sciences. But what are these standards and how sacrosanct are they? Does anthropic multiverse cosmology rest on evaluation criteria that conflict with (...) and go beyond those ordinarily accepted, so that it constitutes an “epistemic shift” in fundamental physics? The paper offers a brief characterization of the modern multiverse and also refers to a few earlier attempts to introduce epistemic shifts in the science of the universe. It further discusses the several meanings of testability, addresses the question of falsifiability as a sine qua non for a theory being scientific, and briefly compares the situation in cosmology with the one in systematic biology. Multiverse theory is not generally falsifiable, which has led to proposals from some physicists to overrule not only Popperian standards but also other evaluation criteria of a philosophical nature. However, this is hardly possible and nor is it possible to get rid of explicit philosophical considerations in some other aspects of cosmological research, however advanced it becomes. (shrink)

During the last decade new developments in theoretical and speculative cosmology have reopened the old discussion of cosmology’s scientific status and the more general question of the demarcation between science and non-science. The multiverse hypothesis, in particular, is central to this discussion and controversial because it seems to disagree with methodological and epistemic standards traditionally accepted in the physical sciences. But what are these standards and how sacrosanct are they? Does anthropic multiverse cosmology rest on evaluation criteria that conflict with (...) and go beyond those ordinarily accepted, so that it constitutes an “epistemic shift” in fundamental physics? The paper offers a brief characterization of the modern multiverse and also refers to a few earlier attempts to introduce epistemic shifts in the science of the universe. It further discusses the several meanings of testability, addresses the question of falsifiability as a sine qua non for a theory being scientific, and briefly compares the situation in cosmology with the one in systematic biology. Multiverse theory is not generally falsifiable, which has led to proposals from some physicists to overrule not only Popperian standards but also other evaluation criteria of a philosophical nature. However, this is hardly possible and nor is it possible to get rid of explicit philosophical considerations in some other aspects of cosmological research, however advanced it becomes. (shrink)

Modern standard big bang cosmology was preceded by a 15-year controversy with the rival steady-state theory of the universe. At a time when cosmologically relevant observations were scarce and cosmology was widely regarded as an immature science, or not a science at all, much of the debate took place by means of arguments that were essentially philosophical. Remarkably, professional philosophers, including some of the key figures of Anglo-American philosophy of science, took an active part in the debate; no less remarkably, (...) the involved astronomers and physicists sometimes listened to them. This article reviews the controversy over the steady-state theory as seen from the perspective of contemporary philosophy of science and offers an appraisal of how and to what extent philosophers and scientists entered a dialogue. -/- . (shrink)

According to modern physics and cosmology, the universe expands at an increasing rate as the result of a “dark energy” that characterizes empty space. Although dark energy is a modern concept, some elements in it can be traced back to the early part of the twentieth century. I examine the origin of the idea of zero-point energy, and in particular how it appeared in a cosmological context in a hypothesis proposed by Walther Nernst in 1916. The hypothesis of a zero-point (...) vacuum energy attracted some attention in the 1920s, but without attempts to relate it to the cosmological constant that was discussed by Georges Lemaître in particular. Only in the late 1960s, was it recognized that there is a connection between the cosmological constant and the quantum vacuum. As seen in retrospect, many of the steps that eventually led to the insight of a kind of dark energy occurred isolated and uncoordinated. (shrink)

The case of Fred Hoyle’s prediction of a resonance state in carbon-12, unknown in 1953 when it was predicted, is often mentioned as an example of anthropic prediction. However, an investigation of the historical circumstances of the prediction and its subsequent experimental confirmation shows that Hoyle and his contemporaries did not associate the level in the carbon nucleus with life. Only in the 1980s, after the emergence of the anthropic principle, did it become common to see Hoyle’s prediction as anthropically (...) significant. At about the same time mythical accounts of the prediction and its history began to abound. Not only has the anthropic myth no basis in historical fact, it is also doubtful if the excited levels in carbon-12 and other atomic nuclei can be used as an argument for the predictive power of the anthropic principle. (shrink)

By 1933, the class of generally accepted elementary particles comprised the electron, the photon, the proton as well as newcomers in the shape of the neutron, the positron, and the neutrino. During the following decade, a new and poorly understood particle, the mesotron or meson, was added to the list. By paying close attention to the names of these and other particles and to the sometimes controversial proposals of names, a novel perspective on this well-researched line of development is offered. (...) Part of the study investigates the circumstances around the coining of “positron” as an alternative to “positive electron.” Another and central part is concerned with the many names associated with the discovery of what in the late 1930s was generally called the “mesotron” but eventually became known as the “meson” and later again the muon and pion. The naming of particles in the period up to the early 1950s was more than just a matter of agreeing on convenient terms, it also reflected different conceptions of the particles and in some cases the uncertainty regarding their nature and relations to existing theories. Was the particle discovered in the cosmic rays the same as the one responsible for the nuclear forces? While two different names might just be synonymous referents, they might also refer to widely different conceptual images. (shrink)

The history of the Greenlandic mineral cryolite is outlined from its discovery in late-eighteenth century to the mid-nineteenth century, when its potential for industrial use was first recognized by the Danish chemist Julius Thomsen. During the 1850s, several attempts were made to exploit cryolite for the production of soda and/or aluminium, of which only the soda process became implemented on an industrial scale. The main part of the paper examines the early cryolite soda manufacture, its chemical basis as well as (...) its industrial significance. The focus is thus the intersection of chemical science and technology. It is argued that Thomsen's process depended intimately on current chemical knowledge, and that, with regard to the science-technology relationship, the cryolite soda manufacture signified a new kind of industrial chemistry. (shrink)

Danish astronomy in the first half of the seventeenth century reflected the enduring legacy of Tycho Brahe and was dominated by his former assistant Longomontanus. This paper focuses on his successor as professor of astronomy, Jørgen From or Georgius Frommius in the Latin version, who was also the second director of the Round Tower observatory in Copenhagen. Before becoming a professor, Frommius travelled to the Netherlands and other countries. The letters from his journey cast light on the training of a (...) young astronomer at the time. He most likely was the first Dane to observe the heavens with a telescope. In the 1640s, he got involved in a controversy with the French astronomer and astrologist Jean Morin, and he later contributed to Pierre Gassendi’s pioneering biography of Tycho Brahe. Although Frommius died at the age of 46, his brief career as professor and astronomer is of interest to national as well as international history of science. (shrink)

By 1870, non-Euclidean geometry had been established as a mathematical research field but was yet to be considered relevant to the real space inhabited by stars and nebulae. It was of much less interest to physicists and astronomers than to mathematicians and philosophers. Although most astronomers took the age-old Euclidean geometry for granted, during the following decades a few of them such as K. F. Zöllner, S. Newcomb and K. Schwarzschild followed in the footsteps of the pioneer N. I. Lobachevsky (...) by seriously considering the possibility that cosmic space might be curved. From the H. Poincaré’s conventionalist perspective the discussion was meaningless since there was no way in which observations or other empirical data could determine the geometry of space. Poincaré’s view was shared by a few astronomers, but its impact on astronomy was limited. The paper examines the question as it was discussed prior to the advent of the general theory of relativity. (shrink)

Ideological considerations have always influenced science, butrarely as directly and massively as in the Soviet Union during the early Cold War period, when cosmology was among the sciences that became politicized. This field of science developed very differently in the Communist countries than in the West, in large measure because of political pressure. Certain cosmological models, in particular of the big bang type, were declared pseudo-scientific and idealistic because they implied a cosmic creation, a concept which was taken to be (...) religious. The result of the ideological pressure was not an independent Soviet cosmology, but that astronomers and physicists abandoned cosmological research in the Western sense. Onlyin the 1960s did this situation change, and cosmology in the Soviet Union began to flourish. The paper reviews the relationship between cosmology and political ideology in the Soviet Union from about 1947 to 1963, and it briefly relates this case to the later one in the People’s Republic of China. (shrink)

Classical thermochemistry is inextricably bound up with the problem of chemical affinity. In 1851, when Julius Thomsen began his career in thermochemistry, the concept of chemical affinity had been in the centre of chemical enquiry for more than a century. In spite of many suggestions, preferably to explain affinity in terms of electrical or gravitational forces, almost nothing was known about the cause and nature of affinity. In this state of puzzling uncertainty some chemists felt it more advantageous to establish (...) an adequate experimental measure of affinity, whatever its nature was. One way of providing affinity with a quantitative description was by means of the heats evolved in chemical processes. (shrink)