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Reflection acoustic microscopy of solid surfaces is generally dominated by interference between a specularly reflected wave and reflected waves associated with excitation of Rayleigh waves in the surface of the sample. The variation of signal as the sample is moved towards the lens is designated V(z). Samples which support Rayleigh waves exhibit oscillations in V(z) associated with this interference. The oscillations can be accounted for either in terms of wave theory, with the waves decomposed into their angular spectrum, or in terms of a ray model, with a geometrical and a Rayleigh contribution.

Failed attempts to understand the anomalous Zeeman effect contributed to the feeling of crisis that by 1924 characterized parts of the physics community. The solution proposed by W. Heisenberg’s ‘core model’ only raised other problems. Another indication was the state of radiation theory and the uncertain relationship between wave theory and the light quantum, a problem that resulted in the controversial BKS (Bohr–Kramers–Slater) theory of 1924. In the wake of this theory, H. Kramers and Heisenberg constructed a formal theory of dispersion that did not rely on electron orbits but only on observable quantities, in agreement with the ‘quantum mechanics’ programme of M. Born. The development culminated with Heisenberg’s paper of August 1925, which marks the end of the Bohr model and the beginning of quantum mechanics. The chapter reconsiders the crisis and the reasons for it, in particular the role of experimental anomalies.

This chapter discusses ferromagnetism, which refers to a magnetic behaviour of which iron is a typical example and which is also found in cobalt and nickel, and in certain alloys and compounds. Topics covered include the Weiss model, the spin-wave theory, spin-wave model and ferromagnetism, the collective electron model, neutron scattering, magnetization curves, and anti-ferromagnetism.

Stressing an interpretive method, this chapter seeks to rethink democratization in the context of the Arab Middle East. It highlights the fierce contests and counter-contests of Western democratization theory. Its interrogation of the ‘transition paradigm’ and ‘third wave’ democratization is based on reference to the key voices in the field. Against this background the chapter looks at the complexity involved in transposing the conventional wisdom and dogmas of such a theory to the Arab context. Interrogation is doubly fierce when ‘word’ (theory) meets ‘world’ (context, practice). A key conclusion is that it is difficult to ‘normativize’ Western democratization theory, suggesting alternative and critical ways of how to treat Western transitology in its ‘travel’ to the Arab context, and noting the ‘open-endedness’ and ‘complexity’ of Arab transitions.

This chapter summarizes the theories of the nature of light, including the corpuscular theory and the wave theory, developed up to the end of the nineteenth century. The early theories (Descartes, Hobbes, and Hooke) are first recalled, and Grimaldi’s observation of the diffraction of light is discussed. Newton’s contributions to optics and his emission theory are then described. An important section is devoted to Huygens’ ‘Treatise on Light’ and his wave theory, and to his explanation of the double refraction of light. During the eighteenth century it was, however, Newton’s theory that was favoured by physicists. Young revived the wave theory at the turn of the nineteenth century, and his theoretical and experimental studies of light interference are related. Fresnel’s diffraction theory is explained in some detail. Finally, a short section is devoted to Einstein’s interpretation of the photoelectric effect and the dual nature of light.

The ways in which the Keplerian turn discussed in the previous chapter manifested itself during the seventeenth century is the subject of this chapter, which examines three particular developments influenced by that turn: the deployment and improvement of telescopes and microscopes; the emergence of new, mechanistic theories of light and color; and the resulting efforts to explain sensation, perception, and cognition on the basis of these new theories. One clear outcome of these efforts was a complete repudiation of the medieval “pictures-in-the-mind” approach to visual cognition, with its emphasis on animating spirits and intentional species, in favor of a more materialist approach based on physical impulses and reactions that correlate with such “pictures” without bearing any resemblance to them.

The chapter opens by contrasting the human capacities for audition as opposed to vision, and the qualities conveyed by sound as opposed to those by light. Despite the general acceptance of wave theory, from the nineteenth century through to today issues of auditory location, transmission and reception remain contested. The ‘auditory scene analysis’ conducted by the novels in this study sees/hears them as participating in this ontological and epistemological uncertainty. Both The Return of the Native and ‘Heart of Darkness’ powerfully evoke densely enveloping closed systems that are examined in terms of their circulating sounds, ‘acoustic pictures’ raised upon the air by sighs in Hardy and whispers in Conrad. Whilst the discussion of ‘Heart of Darkness’ shows that it is an individual voice, and particularly its ‘cry’, which provides a guiding thread for Marlow, when the chapter moves on to sound in Nostromo it is the ambient noise of a historically evolving modernity that carries the theme of the reach of ‘material interests’. Sounds, conceived as units of shock, provide the agitated fabric of this novel of jolts and collisions.

Building on the work of Leonhard Euler, Thomas Young advanced the wave theory of sound and light. This chapter describes how Young found his way to music against the strictures of his Quaker milieu. His new-found passions for music and dance informed his studies of sound and languages. His early work on the accommodation of the eye remained a touchstone for his later scientific development. At many points, his understanding of sound influenced and shaped his approach to light, including the decisive experiments that established its wave nature. His early investigations into the sounds of pipes led him to make an acoustic analogy that could explain optical phenomena such as Newton’s rings. He introduced a new system of temperament and used the piano as a scientific instrument. His comprehensive Lectures on Natural Philosophy included many plates that juxtaposed acoustic and optical phenomena. When Young turned to the decipherment of Egyptian hieroglyphics, he relied on sound and phonology. His final suggestions about the transverse nature of light waves again turned on the comparison with sound. Throughout the book where various sound examples are referenced, please see http://mitpress.mit.edu/musicandmodernscience (please note that the sound examples should be viewed in Chrome or Safari Web browsers).

This chapter examines the role played by probabilities on each of the major approaches to understanding quantum mechanics. It is argued that the sorts of considerations brought up in previous chapters, having to do with limitations on precise knowledge of physical states, and the result of applying dynamical evolution to agents’ degrees of belief about those states, have a part to play on each of those approaches. The chapter includes an introduction to the basic formalism of quantum mechanics.

In this chapter, the neutron inelastic scattering spectrum is calculated for a variety of magnetic systems. A number of isolated magnetic systems are considered, including single-ion crystal field and intermultiplet excitations, and magnetic clusters. Linear spin-wave theory, a method for calculating the collective spin dynamics in magnetically ordered systems, is outlined and applied to ferromagnets and antiferromagnets both with and without anisptropy. The Random Phase Approximation (RPA) method for the generalized susceptibility is presented and applied to calculate the spectrum of crystal field excitons in praseodymium. The nature of the spin excitations in itinerant magnets is described, and the generalized susceptibility is calculated in the RPA for itinerant electrons with echange correlations. General features of the spin dynamical response in quantum magnets are described, and illustrated by the magnetic spectra of quantum spin chains.

Chapter 5 is devoted to the properties of the metallic bond and semiconductors. The Drude–Lorentz free-electron model is discussed together with its applications. The Hall effect demonstrates the need for a refinement of the theory, which leads into a study first of the wave-mechanical free-electron theory, density of states and the Fermi–Dirac distribution. Then, it is followed by the band theory of metals, semiconductors and superconductors. Einstein and Debye models for heat capacity are compared. Fuel cells, batteries and solar cells are studied and their properties compared. The physical and structural characteristics of the metallic bond are discussed. Alloy systems are treated, particularly the Ag–Cd, Cu–Au and Cu–Zn systems. Their characteristics are discussed in terms of the Hume-Rothery rules and their explanation in band theory.

Though Isaac Newton walked out of the only opera he ever attended, music had a significant place in his work. As an undergraduate, Newton closely studied music in its quadrivial context during the crucial year in which he initially formulated his ideas about gravitation and physics. Much later, he used musical concepts to formulate his description of spectral colors by imposing a musical octave on the spectrum. In his studies of the colors of Newton’s rings, however, he observed that the spectral colors seem to span a major sixth, not an octave. He attempted to understand this in terms of cube roots and squares, reminiscent of Kepler’s Third Law in astronomy. By thus arguing away the troublesome discrepancy between an octave and a sixth, Newton did not allow himself to confront the importance of this discrepancy. This musical error may have kept him from realizing the degree of the relation between the wave theory of sound (which he had pioneered) and its application to light. Throughout the book where various sound examples are referenced, please see http://mitpress.mit.edu/musicandmodernscience (please note that the sound examples should be viewed in Chrome or Safari Web browsers).

This chapter focuses on London composer Nicola Sampieri and his “Concert upon an Entire New Plan,” given at the Hanover Square Rooms and elsewhere from 1798. Sampieri’s “New Plan” employed “numerous and beautiful transparencies” to present natural scenes, both mundane and meteorological, with music composed expressly to represent these natural phenomena. Sampieri’s compositions for the fortepiano encouraged listeners to experience correspondences between what they saw and heard. Lockhart argues that Sampieri’s endeavors reflected renewed scientific interest in the analogy between tones and colors, as in the famed experiments of Thomas Young, which demonstrated that light and sound behaved according to a single principle of wave-based movement. Sampieri’s “Concert on a New Plan” provides a link between the pictorial entertainments of eighteenth-century London, and the familiar natural and cosmological imagery of nineteenth-century symphonic program music, such as Mendelssohn’s The Hebrides. Lockhart re-balances the long-held notion of ca. 1798 London as visual-centric, attesting instead to a broad interest in engaging the eyes and the ears together, and an investment in analogical thinking both within art and within science.

Despite its intuitive appeal, classical mechanics is just as fraught with conceptual difficulties and problems of interpretation as its quantum replacement. The problems just happen to be rather less obvious, and so more easily overlooked or ignored. Quantum mechanics was born not only from the failure wrought by trying to extend classical physical principles into the microscopic world of atoms and molecules, but also from the failure of some of its most familiar and cherished concepts. To set the scene and prepare for what follows, this Prologue highlights some of the worst offenders, including: space and time; force and energy; the troublesome concept of mass; light waves and the ether; and atoms and the second law of thermodynamics.

This chapter argues that Wheatstone’s achievements in the fields of acoustics and long-distance communication were the direct result of his early education in musical instrument building. Jackson begins by considering the scientist’s early career in light of the particular culture of music- and scientific showmanship based on and around the Strand, where his father had a musical-instrument shop. Jackson takes us from “Charley Wheatstone’s Clever Tricks” through the Kaleidophone and other devices investigating sound-light analogies and the wave properties of sound. From there we move to Wheatstone’s early experiments in resonance, in which the violin bows, flutes, bassoon reeds and tuning forks strewn about Wheatstone’s musical instrument shop became quite literally instruments of science, generating new acoustic knowledge. Jackson concludes by considering Wheatstone’s work during the 1830s on reeds and reed-pipes, which resulted not only in an early speaking machine (observed with great interest by a young Alexander Graham Bell), but also in his most famous musical invention, the concertina.

The Quantum Cookbook shows that whilst quantum mechanics is mathematically challenging, some basic knowledge and a bit of effort will carry you a long way. It also explains how quantum mechanics was derived from the physics. The abstract formalism based on state vectors in Hilbert space was introduced only when it was deemed desirable to lend the theory greater mathematical consistency, and to reject some of its historical baggage. The best way to come to terms with this formalism is to understand how and why it came about. Debates about interpretation continue to this day and, by providing some historical context, you should get the impression that any lack of comprehension of its meaning on your part is absolutely not your fault. Quantum mechanics challenges our comprehension of what any (and all) scientific theories are meant to be telling us about the nature of reality. It’s okay to have doubts.

This chapter examines the strategic use of the gender term by Anglo-American feminists of the 1970s. Through examining key texts of feminist thinkers of that period the chapter explores the different ways the gender discourse was deployed in so-called second-wave feminist theory. It pays particular attention to the references to Money’s and Stoller’s work found in these texts, and how each thinker used, modified, and remobilized the gender apparatus. The chapter addresses the biopolitical implications of these appropriations and remobilizations, especially regarding the extent to which feminists became unwitting interlocutors of biopolitics by failing to question the raced, classed, and sexed disciplinary origins of gender, and the violence it facilitated toward intersex and trans-people.