It has been shown that for the Reissner-Nordström solution to the vacuum Einstein field equations charge, like mass, has a unique space-time signature (Marsh, Found. Phys. 38:293–300, 2008). The presence of charge results in a negative curvature. This work, which includes a discussion of effective mass, is extended here to the Kerr-Newman solution.

Charge, like mass in Newtonian mechanics, is an irreducible element of electromagnetic theory that must be introduced ab initio. Its origin is not properly a part of the theory. Fields are then defined in terms of forces on either masses—in the case of Newtonian mechanics, or charges in the case of electromagnetism. General Relativity changed our way of thinking about the gravitational field by replacing the concept of a force field with the curvature of space-time. Mass, however, remained an irreducible (...) element. It is shown here that the Reissner-Nordström solution to the Einstein field equations tells us that charge, like mass, has a unique space-time signature. (shrink)

This book contains the material for a first course in pure model theory with applications to differentially closed fields.

This almost self-contained introduction to higher recursion theory is essential reading for all researchers in the field.

Over many centuries, the homing pigeon has been selectively bred for returning home from a distant location. As a result of this strong selective pressure, homing pigeons have developed an excellent spatial navigation system. This system passes through the hippocampal formation, which shares many striking similarities to the mammalian hippocampus; there are a host of shared neuropeptides, interconnections, and its role in the storage and manipulation of spatial maps. There are some notable differences as well: there are unique connectivity patterns (...) and spatial encoding strategies. This review summarizes the comparisons between the avian and mammalian hippocampal systems, and the responses of single neurons in several general categories: location and place cells responding in specific areas, path and goal cells responding between goal locations, context-dependent cells that respond before or during a task, and pattern, grid, and boundary cells that increase firing at stable intervals. Head-direction cells, responding to a specific compass direction, are found in mammals and other birds but not to date in pigeons. By studying an animal that evolved under significant adaptive pressure to quickly develop a complex and efficient spatial memory system, we may better understand the comparative neurology of neurospatial systems, and plot new and potentially fruitful avenues of comparative research in the future. (shrink)

Since locke, introspection has been generally defined as a form of observation. this is true, for example, of the classical tradition in psychology exemplified by wundt and titchener. recent experimental work by cognitive psychologists continues to treat introspection as a mode of observation while denying its alleged success in identifying cognitive processes. besides psychologists, philosophers such as james, ryle, and quinton are discussed, and they, too, define introspection as a type of observation analogous to perception. the present article calls attention (...) to other concepts of introspection that are important but that have figured less prominently in the history of philosophy and psychology. it is agreed here that, so far as the goals of self-knowledge and self-control are concerned, a concept of introspection other than that of observation is the significant one. explicating the nature of this alternative concept of introspection and its relevance for self-knowledge is the major aim of the article. (shrink)

This is the first comprehensive interpretive and critical analysis of the thought of one of America's foremost phiolosophers and psychologists- William James.

The notion of a weakly scattered theory T is defined. T need not be scattered. For each a model of T, let sr() be the Scott rank of . Assume sr() ≤ ω\sp A \sb 1 for all a model of T. Let σ\sp T \sb 2 be the least Σ₂ admissible ordinal relative to T. If T admits effective k-splitting as defined in this paper, then θσ\cal Aθ\cal A$ a model of T.

As fundamentalist religious thought strengthens its hold on U.S. politics and increases its role in politics around the world, enlightened values that form the very foundation of modern society are coming under attack. This essay explores some ramifications of these current conflicts.

This study explores linkages between what Chinese managers generally know about environmental issues, how strongly they value environmental protection, and different types of behaviours/actions they may take within their organizations on behalf of the environment. From a sample of 305 managers in Guangzhou and Beijing, it was found that both environmental knowledge and values are more predictive of more personal managerial behaviours, such as keeping informed of relevant company issues and working within the system to minimize environmental impacts, than more (...) overt behaviours. Moreover, for these more personal actions, environmental knowledge and values were found to have both main and interactive effects. By comparison, it was found that both environmental values and knowledge had additive effects on managerial tendencies to initiate new programs within their domain of responsibility. Only environmental values was found to have a modest influence environmental advocacy. (shrink)

The lambda model of servocontrol seems superior to the alpha model in terms of dealing with the mechanical complexities of nonlinear and multiarticular muscles. Both, however, can be trivialized by noting that the “control variable” may simply be the sum of descending influences at propriospinal interneurons in the case of the lambda model or in the muscles themselves in the case of the alpha model. The notion that the brain explicitly computes output in terms of any such control variables may (...) be an engineering metaphor, useful for conceptual understanding but not for generating predictive hypotheses about higher motor circuitry. (shrink)

This paper investigates the characteristics of firms which have underrepresented groups in top management positions and those which do not. It is argued that profiles of these characteristics will be different for firms with minorities vs. women and that these profiles will be different depending on whether representation is by board membership or through officerships. A discriminant analysis found both similarities and differences in variables that were associated with these different forms of representation. It was found, for example, that size (...) is associated with representation for both minorities and women, whereas high advertising intensity is associated with firms with women on board, but not as officers. Other findings and the implications of the study are discussed. (shrink)

Contents: Recursive Enumerability and the Jump Operator; On the Degrees Less Than 0'; A Simple Set Which Is Not Effectively Simple; The Recursively Enumerable Degrees Are Dense; Metarecursive Sets (with G Kreisel); Post's Problem, Admissible Ordinals and Regularity; On a Theorem of Lachlan and Marlin; A Minimal Hyperdegree (with R O Gandy); Measure-Theoretic Uniformity in Recursion Theory and Set Theory; Forcing with Perfect Closed Sets; Recursion in Objects of Finite Type; The a-Finite Injury Method (with S G Simpson); Remarks Against (...) Foundational Activity; Countable Admissible Ordinals and Hyperdegrees; The 1-Section of a Type n Object; The k-Section of a Type n Object; Post's Problem, Absoluteness and Recursion in Finite Types; Effective Bounds on Morley Rank; On the Number of Countable Models; Post's Problem in E-Recursion; The Limits of E-Recursive Enumerability; Effective Versus Proper Forcing. (shrink)

Problems with the conceptual foundations of quantum mechanics date back to attempts by Max Born, Niels Bohr, Werner Heisenberg, as well as many others in the 1920s to continue to employ the classical concept of a particle in the context of the quantum world. The experimental observations at the time and the assumption that the classical concept of a particle was to be preserved have led to an enormous literature on the foundations of quantum mechanics and a great deal of (...) confusion then and now among non-physicists and students in any field that involves quantum theory. It is the historical approach to the teaching of quantum mechanics that is at the root of the problem. Spacetime is the arena within which quantum mechanical phenomena take place. For this reason, several Appendices are devoted to the nature of spacetime as well as to topics that can help us understand it such as vacuum fluctuations, the Unruh effect and Hawking radiation. Because of the success of quantum mechanical calculations, those who wish to understand the foundations of the theory are often given the apocryphal advice, "just ignore the issue and calculate". It is hoped that this book will help dispel some of the dismay, frustration, and confusion among those who refuse to take to heart this admonition. (shrink)

James argued that time is a sensation, and the main point of this paper is to deny that claim. The concept of the specious present is explained, indicating how it clarifies the concept of "the present moment." But neither it nor an argument used by Mach and James show time to be a sensation. The analysis presented here requires distinguishing concepts of sensation from concepts of temporal relations. James' view is really a theory that time-as-duration is sensed. But this assumes (...) that the description of time as sensed is also a description of time as an objective property of independent events. This is nowhere established, and making it plausible is a recurrent problem for philosophies like neutral monism and radical empiricism. (shrink)