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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 led to almost the same results as Maxwell’s. But whereas Maxwell’s field theory heralded a revolution in physics, Lorenz’s alternative was largely forgotten and soon relegated to a footnote in the history of physics. In part based on archival material and other sources in Danish, this paper offers a detailed contextual account of Lorentz’s theory and its reception in the physics community. Moreover, it includes a brief introduction to other of Lorenz’s scientific contributions and discusses the reasons why his electrical theory of light failed to attract serious interest.

The case of the formation of a high-depth cumulonimbus cloud with a waterspout over the Gulf of Finland is considered. Characteristics of the developing cloud are investigated, and a microphysical structure of the cloud has been obtained from the results of radar observations. The close relationship between radar and electrical characteristics of the thunderstorm is revealed. Studies were conducted to check the compliance of the cloud characteristics to electrical theory of tornado (spout) formation.

Implantation is the key process in the modern semiconductor process which forms the basic device cell by different doping ditribution, depth, angle and element type. They are the key factors to affect the transistor performance, but the implantation-related defect is invisible by the normal failure analysis method. Then electrical analysis and verification is necessary to visualize this kind of defect. Electrical theory is important in this kind of failure analysis to indirectly proven the problematic process. The transistor body effect is a well know effect which is utilized in some kind of IC design to change the transistor Vth for certain purpose. But nobody uses this effect for the implantation-related failure analysis since the implant itself is complex and is not ideally uniform as the theory model. In this paper, implantation-related defect was successfully identified by the application of transistor body effect combined with nanoprobing on the localized structure.

In printing, particularly of newspapers, it was the controllability of electric motors which was the particular advantage. The papers had shown steady growth in their circulations in the nineteenth century, which was partly due to more universal education, but also (in Britain at any rate) the removal of the stamp tax. Just as important, if not more so, was the use of the railways to distribute the papers in time for breakfast and, crucially, the ability to print large numbers very quickly.

To publish in the Annalen was almost a necessity for any physicist hoping for a university career. With few exceptions, all of the established physicists published there, most of them regularly. The journal tells us a good deal about the German researchers and the nature of their interests and work in the middle of the century. In an important respect, it was a different journal than the one Poggendorff began editing twenty some years before. New foreign physics in translations and reports still had a prominent place in it, but the German physics appearing there was no longer in its shadow. The Annalen now regularly published work by German physicists that equaled, and occasionally surpassed, the best work by foreign physicists. At the same time, German work was gaining recognition abroad.

Following major discoveries in electricity and electromagnetism in the early nineteenth century, electrical research underwent a strong, combined experimental and theoretical development through the second half of the century. Nearly all of the leading physicists in Germany worked extensively in the subject. In this chapter, we take up Weber’s continuing research in electrodynamics, culminating in a comprehensive theory of physics, and Clausius’s new fundamental law of electrodynamics. The mechanical theory of heat continued to be of wide interest to German physicists. We follow Clausius’s ongoing work on the subject, now directed to the molecular motions responsible for heat. We also take up Kirchhoff’s research on the mechanical theory of heat together with his work on elasticity theory. All of these examples of work illustrate the growing theoretical connectedness of physics. We look at the university positions in which Weber, Clausius, and Kirchhoff carried out their theoretical researches.

Mathematicians and physicists generally worked in parallel, with points of contact, formal as well as informal. Mathematicians contributed to the work of theoretical physics in ways that did not appear as publications on theoretical physics under their own names. Physicists knew that to do serious theoretical work they needed a sound mathematical preparation, and they would sometimes ask mathematicians for help with their problems. Through their teaching, mathematicians helped physicist in their work in another way. Physicists did not do original research in pure mathematics, but they were capable of adapting results of research by their mathematical colleagues to physical uses. Near the end of our period, Wien thought that theoretical physics in Germany had all but died out, and that for it to recover mathematicians needed to apply themselves to physics, as they had in the past. In this chapter, we look at work in mathematical physics by the mathematicians Gauss, Dirichlet, Riemann, and Carl Neumann.

There is a great need to explore and develop non-destructive testing methods of concrete to ensure proper curing and it possesses required strength in construction and in service. Limited experiments using electrical methods have been reported in the literature to explore the relationship between the electrical properties and quality of concrete. This study was designed to develop experimental methods that employ the relationship between the electrical and mechanical properties of cement concrete. Concrete is an insulating material from the electrical point of view and large volume of theory and experimental techniques are available to study the insulating properties of materials used in electrical and electronic equipments. This study was oriented to examine whether those theories and experimental techniques, could be applied to concrete, with suitable modifications to its specific nature and properties. To facilitate this objective, several equivalent circuits were investigated to represent concrete as an insulating material. Simple measurement of resistivity alone has been undertaken by several previous investigators and it was felt, as confirmed by our own investigations, that this information is not sensitive enough. Therefore, a more sophisticated method based on fundamental electrical theory was developed. These experiments, conclusions drawn, proposal for a diagnostic method and possibility of future developments are discussed in this paper.

Because the over-voltage failure often occurs in the computer room, which is caused by the centerline cut in the case of three-phase load current unbalanced, and is brought by high-order harmonic. So we calculated, analysised and proved its cause and harm in electrical theory, and we have put forward some effective countermeasure to prevent the over-voltage.

For speech and hearing professionals who rely on and use electrical equipment to record and manipulate human biosignals, a poor appreciation of basic electrical theory may (a) inhibit their capacity to use novel instrumental approaches creatively and/or (b) prevent the correct interpretation of instrumental outputs. The purpose of this paper is to provide the practicing clinician with a non-mathematical tutorial on select topics of electricity, including force fields, voltage, current, resistance, Ohm's Law, and basic circuit configurations. The author's intent is directed toward demystifying basic concepts and principles of electricity, allowing the reader to feel more comfortable dealing with electrical applications in the workplace.

This paper analyses the fraught relationship between physics and the ‘occult sciences’ in the decades around 1900. For some, there was no relationship at all; for others there was a relationship but they did not agree on what it looked like. Many physicists converged with spiritualists, theosophists, and others in interpreting X-rays, the electrical theory of matter, and other aspects of the ‘new’ physics as powerful ways of rendering psychic and occult effects scientifically more understandable. However, they were opposed by commentators on physics who agreed that there was a relationship between the ‘new’ physics and psychical research but that these were two manifestations of a worrying drift of physics into metaphysics and religion. More redoubtable critics were the psychologists who denied that physicists had the experience or experimental skill to cope reliably with the psycho-physical phenomena encountered in psychical research. This paper shows that physicist–psychical researchers were content to ally the ‘new’ physics with religion because it helped vanquish awkward associations with materialism. They also tried to justify the value of their experimental skills by appealing to their expertise in investigating subtle physical effects and ability to create tests that respected the delicate conditions of seances.

For a very long time, arguments supporting the neuro-humoral theory, produced by the pharmacologist Henri Dale, did not convince one of the main supporters of the electrical theory, the neurophysiologist John C. Eccles. This article gives a reminder of certain technical elements of this debate between two giants, which remains one of the most symbolic arguments in the history of neurosciences. The difficulties of the cholinergic transmission often betrayed the scepticism concerning the possibility of a functional approach based on neurochemistry.; Pendant très longtemps, les arguments en faveur de la théorie neuro-humorale avancés par le pharmacologue Henri Dale ne vont pas convaincre l'un des principaux partisans de la théorie électrique, le neurophysiologiste John C. Eccles. On propose ici de rappeler quelques éléments techniques de ce débat entre les deux géants, qui demeure l'un des plus emblématiques de l'histoire des neurosciences. Les difficultés de la transmission cholinergique trahissaient souvent le scepticisme d'alors quant à la possibilité même de l'approche fonctionnelle en neurochimie.

This paper describes the US Naval Academy's outreach program called Summer Seminar, which offers the opportunity for high school seniors to participate in one of three six-day sessions to experience life as a midshipman, both academically and otherwise. This paper focuses on the workshop on electrical engineering in 2005, wherein approximately 360 of the total 1,855 high school students attended. The electrical engineering workshop began with an introduction to the fundamentals of electrical theory and led to several contemporary signal processing examples. These included digitized music and state-of-the-art biometric systems. The paper briefly describes each individual activities that incorporate active learning in the electrical engineering workshop

Ever since the 17th century, European thinkers have valued ‘rationality’ at the expense of ‘reasonableness’: the current crisis about postmodernity is one by-product of that obsession. Yet, from garden design and literature to electrical theory and development economics, it can be helpful to restore the balance between these two aspects of Human Reason. In this way, we can recapture the practical wisdom of Aristotle, and recognize the importance of clinical understanding as contrasted with theoretical explanation.

Bejan’s constructal theory is explored for a paradigm problem in electrical theory, analogue of a wide range of transport problems involving flow subject to a Ohm’s Law model. The equi-potential optimisation is derived and generalised to further functional behaviour of resistances. The original case illustrates the power of Bejan’s asymptotic-intersection method.

This paper discusses the problems of cavitation which are associated with sonochemistry. It is concluded that the hot-spot theory is not sufficient to accommodate all experimental data and the alternative is a new electrical theory of cavitation phenomena.

After a short description of the disastrous effects of thetornado which struck the Venice lagoon on September 11, 1970, the principaltheories which in the centuries tried to account for the origin of suchterrible vortexes, are reviewed. In particular, some remarks are given aboutthe electrical theory of the tornadoes. It seems to the author that some featureswould be explained in a simple way by considering the tornado as aconvectivo cell with electric currents of high intensity. Finally, after recallingthe meteorological conditions preceding the tornado of September 11,its chief features are described.

Summary John Hughlings Jackson is widely credited with the first electrical theory of epilepsy (1873), which was confirmed by the experimental studies of Hitzig and Ferrier. His views are summarised in his famous Lumleian lectures to the Royal College of Physicians in 1890. Robert Bentley Todd, however, had earlier developed an electrical theory of epilepsy, which he presented in his own brilliant Lumleian lectures to the Royal College of Physicians in 1849. Todd was influenced by the electrical discoveries of his contemporary, Michael Faraday, and thought of the brain as having battery like properties that led to the sudden discharge of electrical energy (nervous force) in epilepsy. Unlike Hughlings Jackson, Todd was an anatomist and physiologist as well as a physician, and he did his own electrical experiments in rabbits to prove his theory, something Hughlings Jackson, who relied on Ferrier for scientific and experimental support, could never have done. There is no mention of Todd's Lumleian lectures in Hughlings Jackson's later lectures and writings, nor in those of Hitzig or Ferrier. Todd's remarkable observations and lectures, and his electrical theory of epilepsy deserve to be drawn to the attention of the medical and scientific community.