This paper describes a now widely forgotten tradition in the nineteenth century which - to borrow a simile used or implied by the actors themselves - may be described as 'spectroscopic portraiture'. Quite unlike the later obsession with numerical precision in wavelength measurement, and also in stark contrast to the contemporary vogue of photographic mapping which presumptuously claimed 'mechanical objectivity', that is avoidance of any human intervention in the recorded data, there was among some spectroscopists a much greater preoccupation (...) with qualitative rather than quantitative aspects. The atlases of the solar spectrum by Cornu, Thollon, and Piazzi Smyth were supposed to convey the subjectively perceived Gestalt of the Fraunhofer lines, at the expense of precision. I shall argue that this was a systematic research programme addressed to a welldefined but small audience of specialists in the new subdiscipline of spectroscopy which was distinct from other practices such as spectrum analysis, which was directed mainly at chemists. Apart from this, the new tradition can also be identified by the dense net of cross-references in the publications of the various members, and by their critique of earlier work. This tradition of spectrum portraiture started with Kirchhoff's 1861-2 high-resolution chromolithographic plates of the solar spectrum, which were printed off a half-dozen different stones in order to render most faithfully the various line intensities. Focusing especially on the tension between representational goals and technical possibilities in the rapidly developing printing industry, I then trace the emerging tradition through its apogee to the close of the nineteenth century. (shrink)

Spectroscopy is a scientific topic at the interface between Chemistry and Physics, which is taught at high school level in relation with its fundamental applications in Analytical Chemistry. In the first part of the paper, the topic of spectroscopy is analyzed having in mind the well-known Johnstone’s triangle of chemistry education, putting in evidence the way spectroscopy is usually taught at the three levels of chemical knowledge: macroscopic/phenomenological, sub-microscopic/molecular and symbolic ones. Among these three levels, following Johnstone’s recommendations the macroscopic (...) one is the most useful for high school students who learn spectroscopy for the first time. Starting from these premises, in the second part of the paper, we propose a didactic sequence which is inspired by the historical evolution of spectroscopic instruments from the first spectroscopes invented by Gustav Kirchhoff and Robert Bunsen in 1860 to the UV–vis spectrophotometers which became common since the 1960s. The idea behind our research is to analyze the conceptual advancements through the history of spectroscopy and to identify the key episodes/experiments and spectroscopic instruments. For each of them, a didactic activity, typically an experiment, is then proposed underlining the relevant aspects from the chemistry education point of view. The present paper is the occasion to reflect on the potentialities of an historical approach combined with a laboratorial one, and to discuss the role of historical instruments and related technological improvements to teach spectroscopy. (shrink)

In this paper I argue that demonstrative induction can deal with the problem ofthe underdetermination of theory by evidence. I present the historical case studyof spectroscopy in the early 1920s, where the choice among different theorieswas apparently underdetermined by spectroscopic evidence concerning the alkalidoublets and their anomalous Zeeman effect. By casting this historical episodewithin the methodological framework of demonstrative induction, the localunderdetermination among Bohr's, Heisenberg's, and Pauli's rival theories isresolved in favour of Pauli's theory of the electron's spin.

We report on the small-scale (0.5 13 h - 1M, a large-scale bias of ~2.0 and a satellite fraction of 12 ± 2 per cent. Thus, these galaxies occupy haloes with average masses in between those of the higher redshift BOSS CMASS sample and the original SDSS I/II luminous red galaxy sample © 2012 The Authors Published by Oxford University Press on behalf of the Royal Astronomical Society © doi:10.1093/mnras/sts314.

We present a one per cent measurement of the cosmic distance scale from the detections of the baryon acoustic oscillations in the clustering of galaxies from the Baryon Oscillation Spectroscopic Survey, which is part of the Sloan Digital Sky Survey III. Our results come from the Data Release 11 sample, containing nearly one million galaxies and covering approximately 8500 square degrees and the redshift range 0.2 < z < 0.7. We also compare these results with those from the publicly (...) released DR9 and DR10 samples. Assuming a concordance Λ cold dark matter cosmological model, the DR11 sample covers a volume of 13 Gpc3 and is the largest region of the Universe ever surveyed at this density. We measure the correlation function and power spectrum, including density-field reconstruction of the BAO feature. The acoustic features are detected at a significance of over 7σ in both the correlation function and power spectrum. Fitting for the position of the acoustic features measures the distance relative to the sound horizon at the drag epoch, rd, which has a value of rd,fid = 149.28 Mpc in our fiducial cosmology. We find DV = at z = 0.32 and DV = at z = 0.57. At 1.0 per cent, this latter measure is the most precise distance constraint ever obtained from a galaxy survey. Separating the clustering along and transverse to the line of sight yields measurements at z = 0.57 of DA = and H =. Our measurements of the distance scale are in good agreement with previous BAO measurements and with the predictions from cosmic microwave background data for a spatially flat CDM model with a cosmological constant. © 2014 The Author Published by Oxford University Press on behalf of the Royal Astronomical Society. (shrink)

Background: Magnetic resonance spectroscopic imaging is a neuroimaging technique that may be useful for non-invasive mapping of brain temperature over a large brain volume. To date, intra-subject reproducibility of MRSI-based brain temperature has not been investigated. The objective of this repeated measures MRSI-t study was to establish intra-subject reproducibility and repeatability of brain temperature, as well as typical brain temperature range.Methods: Healthy participants aged 23–46 years were scanned at two time points ~12-weeks apart. Volumetric MRSI data were processed by (...) reconstructing metabolite and water images using parametric spectral analysis. Brain temperature was derived using the frequency difference between water and creatine for 47 regions of interest delineated by the modified Automated Anatomical Labeling atlas. Reproducibility was measured using the coefficient of variation for repeated measures, and repeatability was determined using the standard error of measurement. For each region, the upper and lower bounds of Minimal Detectable Change were established to characterize the typical range of TCRE values.Results: The mean global brain temperature over all subjects was 37.2°C with spatial variations across ROIs. There was a significant main effect for time [F = 37.0, p < 0.0001] and for brain region [F = 2.66, p < 0.0001]. The time*brain region interaction was not significant [F = 0.80, p = 0.83]. Participants' TCRE was stable for each ROI across both time points, with ROIs' COVrep ranging from 0.81 to 3.08% ; majority of ROIs had a COVrep <2.0%.Conclusions: Brain temperature measurements were highly consistent between both time points, indicating high reproducibility and repeatability of MRSI-t. MRSI-t may be a promising diagnostic, prognostic, and therapeutic tool for non-invasively monitoring brain temperature changes in health and disease. However, further studies of healthy participants with larger sample size and numerous repeated acquisitions are imperative for establishing a reference range of typical brain TCRE, as well as the threshold above which TCRE is likely pathological. (shrink)

Electronegativity is a quantified, typical chemical concept, which correlates the ability of chemical species to attract electrons during their contact with other species with measurable quantities such as dissociation energies, dipole moments, ionic radii, ionization potentials, electron affinities and spectroscopic data. It is applied to the description and explanation of chemical polarity, reaction mechanisms, other concepts such as acidity and oxidation, the estimation of types of chemical compounds and periodicity. Although this concept is very successful and widely used, and (...) in spite of the fact that it is still subject to scientific investigations, neither a more than intuitive definition nor a generally accepted, logically clear and standardized quantification model has been developed. In the present work, electronegativity is presented and discussed with respect to its main conceptual and operational continuities and discontinuities. We try to analyze the epistemological status of electronegativity, conceived as a typical notion of chemical sciences. Under ‘epistemological status’ we subsume the issues of its reference, its historical persistence, and the relationship between its measurement and quantification. (shrink)

Philosophers have long debated ‘substrate’ and ‘bundle’ theories as to how properties hold together in objects ― but have neglected to consider that every chemical entity is defined by closure of relationships among components ― here designated ‘Closure Louis de Broglie.’ That type of closure underlies the coherence of spectroscopic and chemical properties of chemical substances, and is importantly implicated in the stability and definition of entities of many other types, including those usually involved in philosophic discourse ― such (...) as roses, statues, and tennis balls. Characteristics of composites are often presumed to ‘supervene on’ properties of components. This assumption does not apply when cooperative interactions among components are significant. Once correlations dominate, then adequate descriptions must involve different entities and relationships than those that are involved in ‘fundamental-level’ description of similar but uncorrelated systems. That is to say, descriptions must involve different semantics than would be appropriate if cooperative interactions were insignificant. This is termed ‘Closure Henri Poincaré. Networks of chemical reactions that have certain types of closure of processes display properties that make other more-complex coherences possible. This is termed ‘Closure Jacques Cauvin.’ Each of these three modes of closure provides a sufficient basis for warranted recognition of causal interaction, thus each of them has epistemological significance. Other modes of epistemologically-important closure probably exist. It is important to recognize that causal efficacy generally depends on closure of relationships of constituents. (shrink)

The discovery of Earth-sized extrasolar planets orbiting distant stars will merit an expansion of the sphere of entities worthy of moral consideration. Although it will be a long time, if ever, before humans visit these planets, it is nevertheless worthwhile to develop an environmental ethic that encompasses these planets, as this ethic reflects on our view of life on Earth and elsewhere. A particularly significant case would be a planet that displays spectroscopic signatures of life, although the discovery of (...) many lifeless planets might itself intensify the value of life on Earth. A derivation of Schweitzer’s general principle of “reverence for life” and similar frameworks are appropriate ethics with which to view extrasolar planets. The development of an ethical framework for extrasolar planets might provide a means to fashion a deeper and more effective environmental ethic for Earth’s biosphere. (shrink)

In the early 1880s, Henri Poincaré discovered an equilibrium figure for uniformly-rotating fluid masses—the pear, or piriform figure—and speculated that in certain circumstances the pear splits into two unequal parts, and provides thereby a model for the origin of binary stars. The contemporary emergence of photometric and spectroscopic studies of variable stars fueled the first models of eclipsing binaries, and provided empirical support for a realist view of equilibrium figures—including the pear—in the cosmic realm. The paper reviews astrophysical interpretation (...) of the Poincaré pear and the Poincaré-Darwin fission hypothesis with respect to research on variable stars from 1885 to 1901. (shrink)

This treatise presents thoughts on the divide that exists in chemistry between those who seek their understanding within a universe wherein the laws of physics apply and those who prefer alternative universes wherein the laws are suspended or ‘bent’ to suit preconceived ideas. The former approach is embodied in the quantum theory of atoms in molecules (QTAIM), a theory based upon the properties of a system’s observable distribution of charge. Science is experimental observation followed by appeal to theory that, upon (...) occasion, leads to new experiments. This is the path that led to the development of the molecular structure hypothesis—that a molecule is a collection atoms with characteristic properties linked by a network of bonds that impart a structure—a concept forged in the crucible of nineteenth century experimental chemistry. One hundred and fifty years of experimental chemistry underlie the realization that the properties of some total system are the sum of its atomic contributions. The concept of a functional group, consisting of a single atom or a linked set of atoms, with characteristic additive properties forms the cornerstone of chemical thinking of both molecules and crystals and Dalton’s atomic hypothesis has emerged as the operational theory of chemistry. We recognize the presence of a functional group in a given system and predict its effect upon the static, reactive and spectroscopic properties of the system in terms of the characteristic properties assigned to that group. QTAM gives physical substance to the concept of a functional group. (shrink)

A superconducting transition temperature as high as 100 K was recently discovered in one monolayer FeSe grown on SrTiO3. The discovery ignited efforts to identify the mechanism for the markedly enhanced Tc from its bulk value of 8 K. There are two main views about the origin of the Tc enhancement: interfacial effects and/or excess electrons with strong electron correlation. Here, we report the observation of superconductivity below 20 K in surface electron-doped bulk FeSe. The doped surface layer possesses all (...) the key spectroscopic aspects of the monolayer FeSe on SrTiO3. Without interfacial effects, the surface layer state has a moderate Tc of 20 K with a smaller gap opening of 4.2 meV. Our results show that excess electrons with strong correlation cannot induce the maximum Tc, which in turn reveals the need for interfacial effects to achieve the highest Tc in one monolayer FeSe on SrTiO3. (shrink)

A hundred years ago the science of spectroscopy, though not yet christened, may be said to have attained its majority and to be just entering on its period of full adult development. It was born, of course, with Newton's explanation of the formation of the spectrum, and for many years thereafter little of importance was added to what he had discovered. It was not, in fact, until the nineteenth century that anything of outstanding importance occurred, and then, in 1802, Wollaston (...) substituted a slit for the round hole through which Newton's sunlight passed into his prism, and thereby not only saw for the first time the dark lines in the solar spectrum but also took the first step towards the perfection of the spectroscope on which all later progress depended. The next step was taken by Fraunhofer who, in 1814, examined the spectrum through a telescope instead of letting it fall on a screen. The last essential improvement—the introduction of the collimator to make the light from the slit parallel before it entered the prism—was introduced in 1839 independently by Simms and Swan, so that before our period begins, the complete spectroscope existed, though it was not to be converted into a spectrograph, for photographing spectra, until much later. (shrink)

We examine the epistemological foundations of a leading technique in the search for evidence of life on exosolar planets. Specifically, we consider the “transit method” for spectroscopic analysis of exoplanet atmospheres, and the practice of treating anomalous chemical compositions of the atmospheres of exosolar planets as indicators of the potential presence of life. We propose a methodology for ranking the anomalousness of atmospheres that uses the mathematical apparatus of support vector machines, and which aims to be agnostic with respect (...) to the particular chemical biosignatures of life. We argue that our approach is justified by an appeal to the “hinge” model of epistemic justification first proposed by as reported by Wittgenstein. We then compare our approach to previous work due to Walker et al. :779–824, 2018) and Cleland :722–729, 2019a; Does ‘life’ have a definition?, Cambridge University Press, New York, 2019b). (shrink)

Summary Apart from hydrogen, helium is the most abundant chemical element in the universe, and yet it was only discovered on the Earth in 1895. Its early history is unique because it encompasses astronomy as well as chemistry, two sciences which the spectroscope brought into contact during the second half of the nineteenth century. In the modest form of a yellow spectral line known as D3, ‘helium’ was sometimes supposed to exist in the Sun's atmosphere, an idea which is traditionally (...) ascribed to J. Norman Lockyer. Did Lockyer discover helium as a solar element? How was the suggestion received by chemists, physicists and astronomers in the period until the spring of 1895, when William Ramsay serendipitously found the gas in uranium minerals? The hypothetical element helium was fairly well known, yet Ramsay's discovery owed little or nothing to Lockyer's solar element. Indeed, for a brief while it was thought that the two elements might be different. The complex story of how helium became established as both a solar and terrestrial element involves precise observations as well as airy speculations. It is a story that is unique among the discovery histories of the chemical elements. (shrink)

We discuss two research projects in material science in which the results cannot be stated with an estimation of the error: a spectroscopic ellipsometry study aimed at determining the orientation of DNA molecules on diamond and a scanning tunneling microscopy study of platinum-induced nanowires on germanium. To investigate the reliability of the results, we apply ideas from the philosophy of models in science. Even if the studies had reported an error value, the trustworthiness of the result would not depend (...) on that value alone. (shrink)

The history of Physical Science appears to exhibit, periodically, a race between the acmulation of data and the ability of its codification to find a natural place for much of the empirical findings. If the codifying scheme is a mathematical theory, capable of interpolation and extrapolation, according to the rules of the particular branch of mathematics employed, the ablest handlers of the theory are frequently confronted with a situation in which mathematical computation alone does not suffice. In such a situation (...) the introduction of symbols, whose interpretation is not direct and simple is resorted to. This symbol is usually involved in a mathematical relation by a species of reasoning, which may be somewhat unfamiliar and remote from customary habits of thought. It is generally accepted as physically valid, if the mathematical formulation which involves it can produce results which account for the mass of data uncovered by experimenters. As an example of such a procedure we may mention the case of the Schrödinger Ψ-symbol, a symbol which was involved in Schrödinger's famous matter wave equation. The successes which such a theory enjoyed, particularly, in its initial stages, in formally relating the relative positions and intensities of spectral lines, with the atomistic concepts of gross matter which were inferred from the data of macroscopic measurement, such as the atomic mass, the electronic charge, Planck quantum of action, etc.,—these successes, gave a certain physical dignity to the Ψ-function itself. This dignity was further enhanced by the disclosure, by Schrödinger, of four functions of the Ψ-symbol which held the same place in the “continuity equation” as the classical charge density and the three components of current density. The successes accompanying this discovery for spectroscopic problems, in particular, are well known to Physicists. (shrink)

ABSTRACT During a visit to Europe in the autumn of 1882, Henry Augustus Rowland, Professor of Physics at Johns Hopkins University, displayed diffraction gratings produced on a ruling engine he had designed and built, which were bigger and much higher quality than any previously made. Some were of a novel type, ruled on concave surfaces, which he used in a simple but equally novel spectroscope that he had devised, to reveal spectral lines in great detail, and by means of photography (...) to record spectral data much more rapidly than previously possible. Over about twenty years Rowland built three ruling engines, published photographic maps of the solar spectrum, compiled a catalogue of the wavelengths of lines in the solar spectrum correlated with laboratory-produced spectra of almost all the chemical elements, and produced and sold the diffraction gratings used by spectroscopists everywhere. For decades after his death Rowland’s ruling engines remained practically the only source of good-quality diffraction gratings. This paper describes and analyses this work of Rowland and of the other men, Theodore Schneider, John Brashear, and Lewis Jewell, who played major roles in it. (shrink)

The discovery of Earth-sized extrasolar planets orbiting distant stars will merit an expansion of the sphere of entities worthy of moral consideration. Although it will be a long time, if ever, before humans visit these planets, it is nevertheless worthwhile to develop an environmental ethic that encompasses these planets, as this ethic reflects on our view of life on Earth and elsewhere. A particularly significant case would be a planet that displays spectroscopic signatures of life, although the discovery of (...) many lifeless planets might itself intensify the value of life on Earth. A derivation of Schweitzer’s general principle of “reverence for life” and similar frameworks are appropriate ethics with which to view extrasolar planets. The development of an ethical framework for extrasolar planets might provide a means to fashion a deeper and more effective environmental ethic for Earth’s biosphere. (shrink)

This volume is the latest in a series of books and articles stretching back more than three decades on a theme quite startling in its claims and implications: that terrestrial life did not originate on Earth but arrived in the form of cells or bacteria from outer space. The idea of “panspermia,” that the seeds of life are spread from planet to planet, dates to the 19th century with the ideas of Lord Kelvin. It was championed by the Swedish physicist, (...) chemist, and Nobelist Svante Arrhenius at the beginning of the 20th century. Once scientists recognized the difficulties of life surviving in the conditions of interplanetary and interstellar space, by the 1960s a neo-panspermia became popular: not life itself, but prebiotic chemicals were the new seeds of life, made more likely by the discovery of numerous complex organic molecules in meteorites, comets, and interstellar molecular clouds. But the difficulties of synthesizing anything more complicated than amino acids in the wake of the famous Miller-Urey experiment in 1953 kept alive the idea that life itself may be spread throughout the universe. At the center of this work is Chandra Wickramasinghe, a research student of the maverick astronomer Fred Hoyle. In 1962 Hoyle became interested in the origin and nature of interstellar dust, in particular as found in dense molecular clouds, and he and Wickramasinghe set to work on the problem. They became convinced that dust could not form inside molecular clouds, but must have originated in the atmospheres of cool stars, protoplanetary discs, or supernova ejecta, a theory now widely accepted. It was the next steps that became increasingly controversial: that the spectroscopic signature of dust was best explained by complex biomolecules such as cellulose; that biomolecules were assembled into still more complex forms inside comets; and that the living cells and bacteria generated there were responsible for the origin of life on Earth. And not only that: Hoyle and Wickramasinghe argued that the delivery of bacteria from space continues, affecting both the origin and the ongoing evolution of life, and may even be responsible for certain diseases on Earth. These theories were not only reported in reputable scientific journals such as Nature, but also in popular books including Lifecloud (1978), Diseases from Space (1979), and Evolution from Space (1981). Biologists were not impressed; Lynn Margulis, not known for the timidity of her own theories such as endosymbiosis, called the first book “wanton, amusing, promiscuous fiction.”. (shrink)

Albert Abraham Michelson (1852-1931), the American optical physicist best known for his precise determination of the velocity of light and for his experiments concerning aether drift, is less often acknowledged as the creator of new spectroscopic instrumentation and new spectroscopies. He devised a new method of light analysis relying upon his favourite instrument – a particular configuration of optical interferometer – and published investigations of spectral line separation, Doppler-broadening and simple high-resolution spectra (1887-1898). Contemporaries did not pursue his method. (...) Michelson himself discarded the technique by the end of the decade, promoting a new device, the ‘echelon spectroscope’, as a superior instrument. High-resolution spectroscopy was taken up by others at the turn of the century using the echelon, Fabry-Pérot etalon and similar instruments. Michelson’s ‘Light Wave Analysis’ was largely forgotten, but was rediscovered c1950 and developed over the following three decades into a technique rechristened ‘Fourier transform spectroscopy’. This paper presents Michelson’s interferometric work as a continuum of personal interests and historical context as an example of 'research technology' and 'peripheral science'. (shrink)

The ArgumentGravitational redshift of spectral lines as one of the three early-known experimental implications of Einstein's general theory of relativity and gravitation was intensively searched for by researchers all over the world, but around 1920 most of the contemporary evidence in the sun's Fraunhofer-spectrum conflicted with the predictions of relativity theory.In 1923 the American astrophysicist Charles Edward St. John announced that his own solar spectroscopic data would force him to retreat from his former skepticism concerning the existence of gravitational (...) redshift. This statement was at the time widely interpreted by scientists and journalists alike as the open confession of a rapid conversion of one of the few remaining serious scientific opponents of Einstein's theory.This paper demonstrates that this illusion of a sudden “Gestalt switch” in St. John's evaluation of data can be dissolved by a careful step-by-step account of St. John's research practice between 1917 and 1923. After a fine-grained diachronic report of the development of St. John's interpretation of his and others' data, the second part of the paper consists in a systematic analysis of the heuristics and arguments used by St. John pro and contra gravitational redshift. (shrink)

During the second half of the twentieth century, the domain of geochemistry has greatly expanded and the field is today often seen as a branch of an extended chemistry of the Earth, called cosmochemistry. This paper is a historical introduction to cosmochemistry in which the wider cosmic aspects are surveyed up to about 1915, when nuclear physics changed the scene. These wider aspects or themes include, firstly, the attempts to determine the relative abundances of the elements, secondly, the extension of (...) geochemistry to include physical geochemistry, thirdly, the study of meteorites and, fourthly, the spectroscopic study of the stars within the astrochemical tradition. Because of the lack of reliable data, a great deal of the protocosmochemistry described in the present paper was speculative. Nonetheless, by 1915 the contours of the cosmochemistry of the future were just visible and the developments here singled out can thus be seen as belonging to the prehistory of modern cosmochemistry. (shrink)

Functionally distinct anatomic subdivisions of the brain can often be only a few millimeters in one or more dimensions. The study of metabolic differences in such structures by means of localized in vivo MR spectroscopy is therefore challenging, if not impossible. In fact, the spatial resolution of chemical shift imaging (CSI) in humans is typically in the range of centimeters. The aim of the present study was to optimize 1H CSI in monkeys and demonstrate the feasibility of high spatial resolutions (...) up to 1.4 ؋ 2 ؋ 1.4 mm3. The obtained spatial resolution permitted the segregation of gray and white matter in the visual cortex based on the concentration of different metabolites and neurotrans- mitters like N-acetylaspartate, glutamate, and creatine. Con- centration ratios of white matter versus gray matter tissue as well as between metabolites matched those reported in the literature from healthy human brain, demonstrating the consis- tency and reliability of the procedure. Magn Reson Med 54: 1541–1546, 2005. © 2005 Wiley-Liss, Inc. Key words: in vivo 1H NMR spectroscopy; spectroscopic imag- ing; chemical shift imaging; spatial resolution; monkey visual cortex.. (shrink)

It is with good reason that the name Rutherford is closely linked with the early history of the alpha particle. He discovered them, determined their nature, and from 1909 used them to probe the structure of the atom. From 1898 to 1902 Rutherford construed alpha radiation as a type of non-particulate Röntgen radiation. On his theory of the locomotion of radioactive particles Rutherford proposed that alpha radiation consisted of negatively charged particles. During 1902 he confirmed the particulate nature of alpha (...) radiation but discovered that these alpha particles were positively charged. Although Rutherford suspected from 1903 that these alpha particles were related somehow with helium, the proof required six long years of investigation. By mid-1908 it seemed certain that the alpha particle possessed two units of the elementary charge. Since the e/m ratio had already been determined for alpha particles, this evidence enhanced the suspected connection with helium. However, this gain and loss of charge was still construed as an ionization effect. Since as late as 1908 gaseous ionization was assumed to involve the gain or loss of a single unit of charge, Rutherford's alleged case of doubly ionized alpha particles was presumably an exception. Yet helium was known to be an inert gas and thus hardly a likely candidate for such exceptional ionization behaviour. To establish the connection, therefore, Rutherford resorted to a spectroscopic test. He collected spent alpha particles shot into a thin glass tube and gradually observed the spectrum of helium. Rutherford had thus been correct in his assumption, but a proper explanation was possible only after the confirmation of the nuclear structure of the atom. (shrink)

Editors’ Note:As a matter of policy, the editors believe that publishing several reviews of selected texts is a valuable exercise which will enable a cross-section of views to be aired. The recently published second edition of the National Academy of Sciences’ report “On Being a Scientist” was considered an appropriate text for such treatment. The reviewer, Kenneth D. Pimple, Ph.D., is a Research Associate at the Poynter Center for the Study of Ethics and American Institutions and a Visiting Lecturer in (...) the American Studies Program, both at Indiana University. He has been involved with training faculty members to teach ethics since 1989 and is the project director of “Teaching Research Ethics: A Workshop at Indiana University,” with funding from the Department of Education’s Fund for the Improvement of Postsecondary Education. Her interests include nerve development and regeneration. Her research is in the area of analytical chemistry and emphasizes spectroscopic techniques. (shrink)

In relativistic mechanics the energy-momentum of a free point mass moving without acceleration forms a four-vector. Einstein’s celebrated energy-mass relation E=mc 2 is commonly derived from that fact. By contrast, in Newtonian mechanics the mass is introduced for an accelerated motion as a measure of inertia. In this paper we rigorously derive the relativistic point mechanics and Einstein’s energy-mass relation using our recently introduced neoclassical field theory where a charge is not a point but a distribution. We show that both (...) the approaches to the definition of mass are complementary within the framework of our field theory. This theory also predicts a small difference between the electron rest mass relevant to the Penning trap experiments and its mass relevant to spectroscopic measurements. (shrink)

A recent article argued that signals from conventional Raman spectroscopy of organic materials are overwhelmed by edge filter and fluorescence artefacts. The article targeted a subset of Raman spectroscopic investigations of fossil and modern organisms and has implications for the utility of conventional Raman spectroscopy in comparative tissue analytics. The inferences were based on circular reasoning centered around the unconventional analysis of spectra from just two samples, one modern, and one fossil. We validated the disputed signals with in situ (...) Fourier‐Transform Infrared (FT‐IR) Spectroscopy and through replication with different lasers, filters, and operators in independent laboratories. Our Raman system employs a holographic notch filter which is not affected by edge filter or other artefacts. Multiple lines of evidence confirm that conventional Raman spectra of fossils contain biologically and geologically meaningful information. Statistical analyses of large Raman and FT‐IR spectral data sets reveal patterns in fossil composition and yield valuable insights into the history of life. (shrink)

In a recent paper in this Journal, one of us argued against placing He above Be in Mendeleiev’s system of the elements. In it the goal was to dispute the notion that in Mendeleiev’s system of the elements the location of He should in fact lie above Be, which has a very similar electronic configuration, rather than above the noble gas column. That paper was based on rather old, Hartree–Fock limit studies on the strikingly limited non-additive contributions in the He3 (...) and He4 systems in contrast with the much larger non-additivity obtained for the Be3, Be4 and Be5 oligomers. In a recent benchmark multireference Averaged Quadratic Coupled Cluster results on Be2 and Be3 we showed that the delocalized non-additive contribution comprises 94 % of the binding energy of Be3. Here we use this and other pertinent information (drawn from the same paper) to conclude that He may not be associated with Be in Mendeleiev’s Table, despite their quite similar spectroscopic ground states. Furthermore, we use the new results to show that the large non-additivity implies that less than 2 % of the Be3 binding is located in each Be pair contained within the Be trimer. The rest of the interaction energy is necessarily delocalized over all three Be atoms. This might actually announce the bulk properties (i.e. “the electron gas”) that in solid-state physics explain the large electric and heat conduction for the solid Be metal. Thus, in the case of beryllium the metallic characteristics are already evident in Be3, a far cry from the monoatomic helium gas. (shrink)

How can a work of art give us clues about scientific aspects? How can chemistry help a painter enhance his creativity and, above all, preserve the original characteristics of his work? Does an artist require scientific knowledge to innovate or, at least, not to be faked? Other symbiotic fields between art and science are: tattoos, as body art with physical and chemical consequences; pigments, as basic materials with interesting historiographical preparations; spectroscopy diagnosis, as very broad and thorough method of analysis (...) ; biosensors, as one of the applications of new pigments. Note also the interconnection between the several possible paths of science and art, which reflect new challenges with enormous potential investigated through a literature review and the application as a case study in an educational inquiry module. (shrink)