Nature's Matrix


Book Description

Landscapes are frequently seen as fragments of natural habitat surrounded by a 'sea' of agriculture. But recent ecological theory shows that the nature of these fragments is not nearly as important for conservation as is the nature of the matrix of agriculture that surrounds them. Local extinctions from conservation fragments are inevitable and must be balanced by migrations if massive extinction is to be avoided. High migration rates only occur in what the authors refer to as 'high quality' matrices, which are created by alternative agroecological techniques, as opposed to the industrial monocultural model of agriculture. The authors argue that the only way to promote such high quality matrices is to work with rural social movements. Their ideas are at odds with the major trends of some of the large conservation organizations that emphasize targeted land purchases of protected areas. They argue that recent advances in ecological research make such a general approach anachronistic and call, rather, for solidarity with the small farmers around the world who are currently struggling to attain food sovereignty.Nature's Matrix proposes a radically new approach to the conservation of biodiversity based on recent advances in the science of ecology plus political realities, particularly in the world's tropical regions.




Scattering Matrix Approach to Non-stationary Quantum Transport


Book Description

The aim of this book is to introduce the basic elements of the scattering matrix approach to transport phenomena in dynamical quantum systems of non-interacting electrons. This approach permits a physically clear and transparent description of transport processes in dynamical mesoscopic systems, promising basic elements of solid-state devices for quantum information processing. One of the key effects, the quantum pump effect, is considered in detail. In addition, the theory for the recently implemented new dynamical source ? injecting electrons with time delay much larger than an electron coherence time ? is offered. This theory provides a simple description of quantum circuits with such a single-particle source and shows in an unambiguous way that the tunability inherent to the dynamical systems (in contrast to the stationary ones) leads to a number of unexpected but fundamental effects.




Nature Matrix


Book Description

Nature Matrix is a gathering of some of Robert Michael Pyle’s most significant, original, and timely expressions of a life immersed in the natural world, in all its splendor, power, and peril Nature Matrix: New and Selected Essays contains sixteen pieces that encompass the philosophy, ethic, and aesthetic of Robert Michael Pyle. The essays range from Pyle’s experience as a young national park ranger in the Sierra Nevada to the streets of Manhattan; from the suburban jungle to the tangles of the written word; and from the phenomenon of Bigfoot to that of the Big Year—a personal exercise in extreme birding and butterflying. They include deep profiles of John Jacob Astor I and Vladimir Nabokov, as well as excursions into wild places with teachers, children, and writers. The nature of real wilderness in modern times comes under Pyle’s lens, as does reconsideration of his trademark concept, “the extinction of experience”—maybe the greatest threat of alienation from the living world that we face today. Nature Matrix shows a way back toward possible integration with the world, as it plumbs the range and depth of experience in one lucky life lived in close connection to the physical earth and its denizens. This collection brings together the thoughts and hopes of one of our most widely read and respected natural philosophers as he seeks to summarize a life devoted to conservation.







From QCD Flux Tubes to Gravitational S-matrix and Back


Book Description

This thesis studies various aspects of non-critical strings both as an example of a non-trivial and solvable model of quantum gravity and as a consistent approximation to the confining flux tube in quantum chromodynamics (QCD). It proposes and develops a new technique for calculating the finite volume spectrum of confining flux tubes. This technique is based on approximate integrability and it played a game-changing role in the study of confining strings. Previously, a theoretical interpretation of available high quality lattice data was impossible, because the conventional perturbative expansion for calculating the string spectra was badly asymptotically diverging in the regime accessible on the lattice. With the new approach, energy levels can be calculated for much shorter flux tubes than was previously possible, allowing for a quantitative comparison with existing lattice data. The improved theoretical control makes it manifest that existing lattice data provides strong evidence for a new pseudoscalar particle localized on the QCD fluxtube - the worldsheet axion. The new technique paves a novel and promising path towards understanding the dynamics of quark confinement.







Financial Economics, Risk And Information (2nd Edition)


Book Description

Financial Economics, Risk and Information presents the fundamentals of finance in static and dynamic frameworks with focus on risk and information. The objective of this book is to introduce undergraduate and first-year graduate students to the methods and solutions of the main problems in finance theory relating to the economics of uncertainty and information. The main goal of the second edition is to make the materials more accessible to a wider audience of students and finance professionals. The focus is on developing a core body of theory that will provide the student with a solid intellectual foundation for more advanced topics and methods. The new edition has streamlined chapters and topics, with new sections on portfolio choice under alternative information structures. The starting point is the traditional mean-variance approach, followed by portfolio choice from first principles. The topics are extended to alternative market structures, alternative contractual arrangements and agency, dynamic stochastic general equilibrium in discrete and continuous time, attitudes towards risk and towards inter-temporal substitution in discrete and continuous time; and option pricing. In general, the book presents a balanced introduction to the use of stochastic methods in discrete and continuous time in the field of financial economics.







The Natures of Science


Book Description

A too swift examination, for the benefit evidently of fairly naive readers, of broad philosophical and historical themes in the development of science. The ten chapters are grouped by pairs under five topical heads, which treat respectively the philosophical, aesthetic, cultural, methodological, scientific nature of science. Mathematical material encountered in the final chapter ("Classical duality in modern physics") is likely to be considered off-putting by many of the intended readers. Rather awkwardly composed, though attractively printed and bound. The author is chairman of the Physics Department at the University of the West Indies. (NW) Annotation copyrighted by Book News, Inc., Portland, OR