Billy Graham and the Age of Anxiety

Billy Graham is one of the most popular and influential religious figures of the American 20th century. This dissertation will examine the reasons for this popularity by considering the relationship between key aspects of Graham’s message and the cultural anxieties that were present in America in the 1950s and 1960s. Focusing on the theme of Graham’s conversion narratives and using theories derived from the social sciences, I will argue that Graham’s success stemmed from his ability to tap into prevailing anxieties and provide a therapeutic response to them. My project will outline a genealogy of both the history of conversion narratives in the United States and the development of social scientific theories to understand those narratives. I will then give an account of Graham’s third conversion narrative, the Forest Home story, and demonstrate the ways in which the story encapsulates Graham’s fundamental message: certainty in the face of doubt. I will next examine Graham’s teachings on gender and sex, and link his message to the anxiety over shifting gender roles in post-War America. Lastly, I will stray from the theme of conversion to examine Graham’s eschatology and how it informed his views on race, politics, and civil religion. On the broadest level, this dissertation contributes to the discussion of the relationship between religious leaders and their culture - more specifically, the ways that religious leaders embody, address, and attempt to defuse cultural anxiety. The narrower objective of the dissertation is to bring to light the ways Graham addressed the anxieties of the 1950s and 60s to obtain fame and power

Magnetic relaxation in metallic films: Single and multilayer structures

The intrinsic magnetic relaxations in metallic films will be discussed. It will be shown that the intrinsic damping mechanism in metals is caused by incoherent scattering of itinerant electron-hole pair excitations by phonons and magnons. Berger [L. Berger, Phys. Rev. B 54, 9353 (1996)] showed that the interaction between spin waves and itinerant electrons in multilayers can lead to interface Gilbert damping. Ferromagnetic resonance (FMR) studies were carried out using magnetic single and double layer films. The FMR linewidth of the Fe films in the double layer structures was found to always be larger than the FMR linewidth measured for the single Fe films having the same thickness. The increase in the FMR linewidth scaled inversely with the film thickness, and was found to be linearly dependent on the microwave frequency. These results are in agreement with Berger's predictions. (C) 2002 American Institute of Physics

Spherical Hartree-Fock calculations with linear momentum projection before the variation.Part I: Energies, form factors, charge densities and mathematical sum rules

Spherical Hartree--Fock calculations with projection onto zero total linear momentum before the variation are performed for the nuclei 4He, 12C, 16O, 28Si, 32S and 40Ca using a density--independent effective nucleon--nucleon interaction. The results are compared to those of usual spherical Hartree--Fock calculations subtracting the kinetic energy of the center of mass motion either before or after the variation and to the results obtained analytically with oscillator occupations. Total energies, hole--energies, elastic charge form factors and charge densities and the mathematical Coulomb sum rules are discussed.Comment: 16 pages, 13 postscript figure

Edge-dependent selection rules in magic triangular graphene flakes

The electronic shell and supershell structure of triangular graphene quantum dots has been studied using density functional and tight-binding methods. The density functional calculations demonstrate that the electronic structure close to the Fermi energy is correctly described with a simple tight-binding model where only the p_z orbitals perpendicular to the graphene layer are included. The results show that (i) both at the bottom and at the top of the p_z band a supershell structure similar to that of free electrons confined in a triangular cavity is seen, (ii) close to the Fermi level the shell structure is that of free massless particles, (iii) triangles with armchair edges show an additional sequence of levels ('ghost states') absent for triangles with zigzag edges while the latter exhibit edge states, and (iv) the observed shell structure is rather insensitive to the edge roughness

Electronic structure of triangular, hexagonal and round graphene flakes near the Fermi level

The electronic shell structure of triangular, hexagonal and round graphene quantum dots (flakes) near the Fermi level has been studied using a tight-binding method. The results show that close to the Fermi level the shell structure of a triangular flake is that of free massless particles, and that triangles with an armchair edge show an additional sequence of levels ("ghost states"). These levels result from the graphene band structure and the plane wave solution of the wave equation, and they are absent for triangles with an zigzag edge. All zigzag triangles exhibit a prominent edge state at the Fermi level, and few low-energy conduction electron states occur both in triangular and hexagonal flakes due to symmetry reasons. Armchair triangles can be used as building blocks for other types of flakes that support the ghost states. Edge roughness has only a small effect on the level structure of the triangular flakes, but the effect is considerably enhanced in the other types of flakes. In round flakes, the states near the Fermi level depend strongly on the flake radius, and they are always localized on the zigzag parts of the edge

A point particle model of lightly bound skyrmions

A simple model of the dynamics of lightly bound skyrmions is developed in which skyrmions are replaced by point particles, each carrying an internal orientation. The model accounts well for the static energy minimizers of baryon number 1≤B≤8 obtained by numerical simulation of the full field theory. For 9≤B≤23, a large number of static solutions of the point particle model are found, all closely resembling size B subsets of a face centred cubic lattice, with the particle orientations dictated by a simple colouring rule. Rigid body quantization of these solutions is performed, and the spin and isospin of the corresponding ground states extracted. As part of the quantization scheme, an algorithm to compute the symmetry group of an oriented point cloud, and to determine its corresponding Finkelstein-Rubinstein constraints, is devised

Gilbert Damping in Magnetic Multilayers

We study the enhancement of the ferromagnetic relaxation rate in thin films due to the adjacent normal metal layers. Using linear response theory, we derive the dissipative torque produced by the s-d exchange interaction at the ferromagnet-normal metal interface. For a slow precession, the enhancement of Gilbert damping constant is proportional to the square of the s-d exchange constant times the zero-frequency limit of the frequency derivative of the local dynamic spin susceptibility of the normal metal at the interface. Electron-electron interactions increase the relaxation rate by the Stoner factor squared. We attribute the large anisotropic enhancements of the relaxation rate observed recently in multilayers containing palladium to this mechanism. For free electrons, the present theory compares favorably with recent spin-pumping result of Tserkovnyak et al. [Phys. Rev. Lett. \textbf{88},117601 (2002)].Comment: 1 figure, 5page

Using Bayes to get the most out of non-significant results

No scientific conclusion follows automatically from a statistically non-significant result, yet people routinely use non-significant results to guide conclusions about the status of theories (or the effectiveness of practices). To know whether a non-significant result counts against a theory, or if it just indicates data insensitivity, researchers must use one of: power, intervals (such as confidence or credibility intervals), or else an indicator of the relative evidence for one theory over another, such as a Bayes factor. I argue Bayes factors allow theory to be linked to data in a way that overcomes the weaknesses of the other approaches. Specifically, Bayes factors use the data themselves to determine their sensitivity in distinguishing theories (unlike power), and they make use of those aspects of a theory’s predictions that are often easiest to specify (unlike power and intervals, which require specifying the minimal interesting value in order to address theory). Bayes factors provide a coherent approach to determining whether non-significant results support a null hypothesis over a theory, or whether the data are just insensitive. They allow accepting and rejecting the null hypothesis to be put on an equal footing. Concrete examples are provided to indicate the range of application of a simple online Bayes calculator, which reveal both the strengths and weaknesses of Bayes factors

Scenarios of habitat management options to reduce predator impacts on nesting waders

1. Wetland ecosystems throughout the world are threatened by drainage and intensification of agriculture. Consequently, many wetland species of conservation concern are now restricted to fewer and smaller sites, and maintaining these species often requires intensive habitat management.  2. In Western Europe, breeding wader populations have declined severely as a result of wetland degradation, but very high levels of predation on eggs and chicks are now preventing population recovery. Wet grassland management for breeding waders has focussed on providing suitable nesting habitats, but the potential for management of landscape features to influence predation rates is largely unknown.  3. Using a 7-year study of breeding lapwing, Vanellus vanellus, and redshank, Tringa totanus, we first identify features that influence nest predation, and then use this information to compare the magnitude of change in nest predation rates that could potentially result from future landscape management scenarios.  4. As lapwing nest predation rates are higher (a) in fields further from patches of tall vegetation, (b) close (<50 m) to field edges in wet fields, (c) further from field edges in dry fields and (d) in areas of low lapwing nesting density, we modelled a series of realistic scenarios in which the area of tall vegetation and the extent and distribution of surface water were varied across the reserve, in order to quantify the magnitude of change in nest predation rate that could potentially have been achieved through management.  5. Modelled scenarios of changes in surface water and area of tall vegetation indicated that reduced surface flooding combined with removal of tall vegetation could result in significant increases in lapwing nest predation rates in areas with low nesting densities and nests in field centres. By contrast a ~20% reduction in nest predation, corresponding to ~100 more chicks hatching per year, is predicted in scenarios with expansion of tall vegetation in areas with high lapwing nest density and nests close to field edges.  6. Synthesis and applications: These management scenarios suggest that, for breeding waders in wet grassland landscapes, creating areas of tall vegetation and concentrating surface flooding (to encourage high nesting densities and influence nesting distribution) can potentially help to reduce the unsustainably high levels of nest predation that are preventing population recovery