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Optical Vortex Beams: Fundamentals and Techniques (Advances in Optics and Optoelectronics)
Par Shiyao Fu, Chunqing Gao. 2023
This book focuses on optical vortices, including beams carrying orbital angular momentum and vector beams. It presents an overview of,…
and the latest research on this novel type of optical beam, which is a hot topic in the domain of modern optics, especially in optical communication and beam manipulation. Summarizing the fundamentals of optical vortices, it discusses their characterization and propagation, and focuses on the generation of vortices such as vortex-arrays, and the detection of vortices and their orbital angular momentum state. It also comprehensively examines the adaptive compensation systems, as well as vector beams and polarization vortices with anisotropic polarization distributions. Further it provides a detailed description of perfect vortices with beam diameters independent of the angular momentum. This book is intended for researchers, engineers and graduate students working in the field of optics and laser beam applications.Mechanics and Geometry of Enriched Continua
Par Luis Espath. 2023
This monograph presents a comprehensive and rigorous new framework for the theoretical description and modelling of enriched continua. In other…
words, continua that exhibit more complex behaviour than their conventional counterparts and, in particular, multicomponent systems. It employs gradient theories, exhibiting multiple transition layers described by phase fields. As a point of departure, we account for multiple continuum kinematic processes, including motion and various phase fields. These gradient theories arise by considering various kinematic processes which are tightly linked to the level of the arbitrariness of the Euler–Cauchy cuts. The surface defining the Euler–Cauchy cut may lose its smoothness along a curve, and the curve may also lose its smoothness at a point. Additionally, we postulate the principle of virtual power on surfaces. Then, the first and second laws of thermodynamics with the power balance provide suitable and consistent choices for the constitutive equations. Finally, the complementary balances, namely the balances on surfaces, are tailored to coincide with different parts of the boundaries of the body. These surface balances are then called environmental surface balances and aid in determining suitable and consistent boundary conditions. Ultimately, the environmental surface power balance is relaxed to yield an environmental surface imbalance of powers, rendering a more general type of boundary condition.A detailed introduction sets the scene for the mathematical chapters that follow, ensuring that graduate students and newcomers can profit from the material presented.Mathematical Aspects of Paradoxes in Cosmology: Can Mathematics Explain the Contemporary Cosmological Crisis?
Par Michal Křížek, Lawrence Somer. 2023
This book provides a mathematical and numerical analysis of many problems which lead to paradoxes in contemporary cosmology, in particular,…
the existence of dark matter and dark energy. It is shown that these hypothetical quantities arise from excessive extrapolations of simple mathematical models to the whole physical universe. Written in a completely different style to most books on General Relativity and cosmology, the important results take the form of mathematical theorems with precise assumptions and statements. All theorems are followed by a corresponding proof, or an exact reference to the proof.Some nonstandard topics are also covered, including violation of the causality principle in Newtonian mechanics, a critical mathematical and numerical analysis of Mercury's perihelion shift, inapplicability of Einstein's equations to the classical two-body problem due to computational complexity, non-uniqueness of the notion of universe, the topology of the universe, various descriptions of a hypersphere, regular tessellations of hyperbolic spaces, local Hubble expansion of the universe, neglected gravitational redshift in the detection of gravitational waves, and the possible distribution of mass inside a black hole. The book also dispels some myths appearing in the theory of relativity and in contemporary cosmology. For example, although the hidden assumption that Einstein's equations provide a good description of the evolution of the whole universe is considered to be obvious, it is just a null hypothesis which has not been verified by any experiment, and has only been postulated by excessive extrapolations of many orders of magnitude.Freezing of Lakes and the Evolution of Their Ice Cover (Springer Praxis Books)
Par Matti Leppäranta. 2023
This book updates the first edition for the status of knowledge in the physics of lake ice and the interactions…
between the ice cover and the liquid water underneath. Since the first edition was written in 2013, there has been a lot of progress in the field, in particular concerning environmental questions and the impact of climate change. Life conditions in ice-covered lakes and practical matters are now brought more into the picture so that the revision also properly serves as a handbook for applications. The author has worked widely with boreal lakes, polar lakes and Central Asian lakes that provides a wide geographical spectrum.Chapter 1 gives a brief overview and presents the research fields. The second chapter contains the classification of ice-covered lakes and observation techniques, especially remote sensing. In Chapter 3, the structure and properties of lake ice are presented including optics and geochemistry. Ice growth and melting are treated in Chapter 4, while the following chapter focuses on ice mechanics with applications to traffic on ice and ice loads. Chapter 6 goes into the exotic environment of pro-glacial lakes. Chapter 7 contains the stratification and circulation of the water body beneath lake ice, Chapter 8 presents the winter ecology of freezing lakes and discusses the lake ice interface toward the society, and Chapter 9 summarizes the climate change impact on lake ice seasons. The book ends into a brief closing chapter and list of references. Research problems for student learning are listed throughout the book. Annexes are included to provide numerical data of constants and standard formulae to help practical calculations and student tasks.Lake ice closely interacts with human living conditions, but people have learnt to live with that and to utilize the ice. In the present time this is true for on-ice traffic and recreation activities. Ice fishing has become a widely enjoyed hobby, and winter sports such as skiing, skating, and ice sailing are popular activities on frozen lakes. The lake ice response to eventual climate warming would appear as a shortening of the ice season due to the increasing air temperature and also as changing of the quality of the ice seasons via changes in ice thickness and structure. The book gives the whole story of lake ice into a single volume. The second, revised edition updates the content based on recent progress in winter limnology and ice physics research and applications. The author has contributed to lake ice research since the 1980s. In particular, his topics have been lake ice structure and thermodynamics, light transfer in ice and snow, ice mechanics in large lakes, and lake ice climatology. Mathematical modeling of ice growth, drift, and decay are covered in this research.This book presents a guide of optical mineralogy for beginners and microscopists who need to brush up their knowledge. It…
allows the fast identification of common rock-forming minerals in a thin section using a polarized light microscope and transmitted plane and cross polarized light. The book summarizes essential principles of optical mineralogy in numerous schemes. It explains, with the aid of more than 1000 microscopic images, how to determine the diagnostic optical characteristics of a mineral in a thin section. Seventy-two mineral plates of sixty-five common rock-forming minerals comprising typical microscopic images in plane and cross polarized light illustrate the most important optical and crystallographic parameters and their diagnostic characteristics and typical appearance in various geological settings. The original approach of the book is to facilitate mineral identification by mineral plates organized according to color in transmitted plane polarized light and, in each color category, according to decreasing maximum birefringence in cross polarized light. In addition, two chapters are devoted to the classification of magmatic and metamorphic rocks and their common mineral parageneses and textures.The book reflects the author’s experience of teaching optical mineralogy in the most efficient way possible to generations of students at the Universities of Heidelberg (Germany), Basel (Switzerland), and Geneva (Switzerland).Principles and Practice of Image-Guided Radiation Therapy of Lung Cancer (Imaging in Medical Diagnosis and Therapy)
Par Jing Cai, Joe Y. Chang, Fang-Fang Yin. 2018
This book gives a comprehensive overview on the use of image-guided radiation therapy (IGRT) in the treatment of lung cancer,…
covering step-by-step guidelines for clinical implementations, fundamental principles and key technical advances. It covers benefits and limitations of techniques as well as quality and safety issues related to IGRT practice. Addresses imaging simulation, treatment planning, verification, and delivery Discusses important quality assurance issues Describes current methods using specialized machines and technologies Jing Cai, PhD, is an Associate Professor of Radiation Oncology at Duke University Medical Center. Joe Y. Chang, MD, PhD, is Professor in the Department of Radiation Oncology at The University of Texas MD Anderson Cancer Center in Houston. Fang-Fang Yin, PhD, is Chief of the Division of Radiation Physics, Professor of Radiation Oncology, and Director of the Medical Physics program at Duke University.Remote and Robotic Investigations of the Solar System
Par C. R. Kitchin. 2018
Interest in and knowledge of the techniques utilised to investigate our solar system has been growing rapidly for decades and…
has now reached a stage of maturity. Therefore, the time has now arrived for a book that provides a cohesive and coherent account of how we have obtained our present knowledge of solar system objects, not including the Sun. Remote and Robotic Investigations of the Solar System covers all aspects of solar system observations: the instruments, their theory, and their practical use both on Earth and in space. It explores the state-of-the-art telescopes, cameras, spacecraft and instruments used to analyse the interiors, surfaces, atmospheres and radiation belts of solar system objects, in addition to radio waves, gamma rays, cosmic rays and neutrinos. This book would be ideal for university students undertaking physical science subjects and professionals working in the field, in addition to amateur astronomers and anyone interested in learning more about our local astronomical neighbours.The Yellow Pad: Making Better Decisions in an Uncertain World
Par Robert E. Rubin. 2023
Robert Rubin, former secretary of the Treasury and co-chairman of Goldman Sachs, shares thoughts on decision-making developed over more than…
six decades in markets, business, government, and politics, and offers readers an astute and original guide for navigating uncertain timesIn 1958, as a college sophomore, Robert Rubin took a class that changed his life. The class was introduction to philosophy, and the professor, Raphael Demos, instilled in his students an idea that was simple yet profound: There is no such thing as certainty. For Rubin, this led to a critically important question: How can we make sound decisions in a fundamentally uncertain world?While serving in some of the most significant roles in markets, business, and government, Rubin has grappled with that question. Time and again, when faced with a high-stakes decision, he turned to his most trusted tool: a simple yellow legal pad. Rubin&’s yellow pad (or more recently, his iPad) became an expression of a larger decision-making philosophy that has both lasted and shaped a lifetime. In The Yellow Pad, Rubin lays out that philosophy with depth and detail, and presents a compelling intellectual framework for confronting some of the most difficult issues we face today.The Yellow Pad contains a former Treasury secretary&’s approach to economic policymaking. A former Goldman Sachs senior partner&’s approach to personal investing and understanding risk. A former director of the National Economic Council&’s approach to managing people in both private- and public-sector organizations. And much more. Yet despite his lifetime of experiences, Rubin remains refreshingly open-minded, interested in exploring ideas rather than promoting ideologies. With its combination of wisdom and relevance, The Yellow Pad is an essential guide for anyone looking to make better decisions in life, work, and public policy.Optical Coherence Tomography (OCT), a method to "see inside of things" without destroying them, has been applied to subjects ranging…
from materials science to medicine. This book focuses on the biomedical application of OCT in dentistry, covering topics from dental materials to clinical practice. Since the introduction of the OCT method in ophthalmology in 1991, and then dentistry in 1998, developments in OCT methods, particularly in biomedical areas, have led to its dissemination worldwide. The chapters of this book cover the basics and recent global advances of OCT in dentistry, including an overview of the method and its use in cariology, restorative dentistry, dental materials, endodontics, pediatric dentistry, orthodontics, prosthodontics, soft oral tissues and nanodentistry. This book will be of interest to both newcomers in the field as well as those already working in OCT, either in research and/or the clinic. It will be of great use in courses on optical imaging applied to biomedical areas, particularly where it can provide real-life examples of the application of OCT.This book summarizes the state-of-the-art advances in the area of computational modelling of molecule-based magnets. Nowadays, various computational tools based…
on DFT, ab initio methods and other techniques are gaining attention in molecular nanomagnets and are successfully used to solve several outstanding problems in this area. This contributed volume discusses the theoretical foundation of the modelling of molecular magnets, starting from fitting the experimental magnetic data of very large molecules to the theory of pseudo-spin Hamiltonian approach and spin-phonon relaxations mechanisms, while it also presents examples of contemporary applications of both transition metal and lanthanide molecular magnets. In addition, the transport characteristics of molecules when placed at an interface and how these assemble on surfaces are also reviewed. This book is a great tool for researchers working in the fields of molecular magnetism and computational/theoretical chemistry and will also benefit graduate students specializing in physical-inorganic chemistry and molecular modelling.Chapter 6 is available open access under a Creative Commons Attribution 4.0 International License via link.springer.com.This book presents advances in the field of rare-earth (R) – transition metal (M) – boron compounds with extensive references.…
Since titanium and scandium do not form compounds with rare-earths, the Sc/Ti-M-B series are additionally presented. In each chapter the crystal structures, the complex physical properties as determined from neutron diffraction, magnetic measurements, resonance studies, transport properties and band structure calculations are critical analyzed. The models used in describing the experimental evidence are also presented. Tables with the main properties of the R-M-B compounds are given and representative data are illustrated in figures. In this way, the book provides state-of-the art knowledge and a valuable analysis of up-to-date results in the field. The technical applications, as permanent magnets, thermoelectric and magnetocaloric devices, hydrogen storage are also highlighted along with the authors insights into future directions in the field. The book is of interest for scientists involved in the development of the field as well as those working in the technical uses of rare-earth compounds.A Great Restlessness: The Life and Politics of Dorise Nielsen
Par Faith Johnston. 2006
Dorise Nielsen was a pioneering feminist, a radical politician, the first Communist elected to Canadaís House of Commons, and the…
only woman elected in 1940. But despite her remarkable career, until now little has been known about her.From her youth in London during World War I to her burial in 1980 in a heroís cemetery in China, Nielsen lived through tumultuous times. Struggling through the Great Depression as a homesteaderís wife in rural Saskatchewan, Nielsen rebelled against the poverty and injustice that surrounded her, and found like-minded activists in the CCF and the Communist Party of Canada. In 1940 when leaders of the Communist Party were either interned or underground, Nielsen became their voice in Parliament. But her activism came at a high price. As a single mother in Ottawa, she sacrificed a close relationship with her family for her career. As a woman in an emerging political organisation, her authority was increasingly usurped by younger male party members. As a committed communist, she moved to Mao's China in 1957 and dedicated her lifeís work to a cause that went seriously awry.Faith Johnston illuminates the life of a woman who paved the way for a generation of women in politics, who tried to be both a good mother and a good revolutionary, and who refused to give up on either.Statistical Physics
Par Nicolas Sator, Nicolas Pavloff, Lenaic Couedel. 2024
This book presents an introduction to the main concepts of statistical physics, followed by applications to specific problems and more…
advanced concepts, selected for their pedagogical or practical interest. Particular attention has been devoted to the presentation of the fundamental aspects, including the foundations of statistical physics, as well as to the discussion of important physical examples. Comparison of theoretical results with the relevant experimental data (with illustrative curves) is present through the entire textbook. This aspect is facilitated by the broad range of phenomena pertaining to statistical physics, providing example issues from domains as varied as the physics of classical and quantum liquids, condensed matter, liquid crystals, magnetic systems, astrophysics, atomic and molecular physics, superconductivity and many more. This textbook is intended for graduate students (MSc and PhD) and for those teaching introductory or advanced courses on statistical physics. Key Features: A rigorous and educational approach of statistical physics illustrated with concrete examples. A clear presentation of fundamental aspects of statistical physics. Many exercises with detailed solutions. Nicolas Sator is Associate Professor at Sorbonne University, Paris, France. He is a member of the Laboratory of Theoretical Physics of Condensed Matter (LPTMC) and his research focuses on the physics of liquids. Nicolas Pavloff is Professor at Paris-Saclay University, France. He is a member of Laboratoire de Physique Théorique et Modèles Statistiques (LPTMS) and his domain of research is quantum fluid theory. Lénaïc Couëdel is Professor at the University of Sasktchewan, Saskatoon, Canada and researcher at CNRS, France. His research area is plasma physics with a focus on complex plasma crystals.Lincoln’s Final Hours: Conspiracy, Terror, and the Assassination of America's Greatest President
Par Kathryn Canavan. 2015
When John Wilkes Booth fired his derringer point-blank into President Abraham Lincoln's head, he set in motion a series of…
dramatic consequences that would upend the lives of ordinary Washingtonians and Americans alike. In a split second, the story of a nation was changed. During the hours that followed, America's future would hinge on what happened in a cramped back bedroom at Petersen's Boardinghouse, directly across the street from Ford's Theatre. There, a twenty-three-year-old surgeon -- fresh out of medical school -- struggled to keep the president alive while Mary Todd Lincoln moaned at her husband's bedside.In Lincoln's Final Hours, author Kathryn Canavan takes a magnifying glass to the last moments of the president's life and to the impact his assassination had on a country still reeling from a bloody civil war. With vivid, thoroughly researched prose and a reporter's eye for detail, this fast-paced account not only furnishes a glimpse into John Wilkes Booth's personal and political motivations but also illuminates the stories of ordinary people whose lives were changed forever by the assassination.While countless works on the Lincoln assassination exist, Lincoln's Final Hours moves beyond the well-known traditional accounts, offering readers a front-row seat to the drama and horror of Lincoln's death by putting them in the shoes of the audience in Ford's Theatre that dreadful evening. Through her careful narration of the twists of fate that placed the president in harm's way, of the plotting conversations Booth had with his accomplices, and of the immediate aftermath of the assassination, Canavan illustrates how the experiences of a single night changed the course of history.Physics of Matter (Manchester Physics Series)
Par George C. King. 2023
Physics of Matter First year core course introductory textbook on the nature of matter that puts the physics before mathematical…
description Physics of Matter is an introductory textbook on the nature of matter, based on a description of gases, liquids, liquid crystals and solids in terms of the forces that bind atoms and molecules together and their thermal motion, that discusses the relationship of these phases of matter to heat and the basic principles of thermodynamics. Physics of Matter is unique in its coverage of material and includes topics that have become important in recent times such as graphene and liquid crystals. Material in the book is reinforced by numerous worked examples in the text and problems and solutions at the end of each chapter, the latter ranging in difficulty from simple exercises to challenging problems. The emphasis is on clarity of exposition and explanation, putting the physics before the mathematical with general physical principles that can be more widely applied being stressed. Published in the Manchester Physics Series, which has the reputation of providing insight, depth, and often details on a subject not found in other textbooks, sample topics covered in Physics of Matter include: Characteristics of atoms (sizes and masses) and Avogadro’s number, the forces that bind atoms and molecules together, and the Lennard-Jones potential Thermal energy, temperature, and the Boltzmann law, covering equations of state, the ideal gas equation, and equipartition of energy Kinetic theory and transport properties of gases, covering molecular collisions, pressure of an ideal gas, the mean free path and diffusion Real gases, including Van der Waals equation of state, virial expansion, critical constants, and heat capacities Reversible processes, entropy, the Carnot cycle, the thermodynamic fundamental relationship, and Gibbs free energy Solids, including crystal structure, elastic moduli and Einstein’s model of heat capacity Liquids, including liquid flow and Bernoulli’s equation, and liquid crystals Physics of Matter is a valuable learning resource for first- and second-year students in physics, chemistry, and engineering, as well as those in adjacent science courses including environmental and biological sciences. The book is written for the subject traditionally called “Properties of Matter.”Ralph W. Yarborough, The People's Senator (Focus on American History Series)
Par Patrick Cox. 2001
Revered by many Texans and other Americans as "the People's Senator," Ralph Webster Yarborough (19031996) fought for "the little people"…
in a political career that places him in the ranks of the most influential leaders in Texas history. The only U. S. Senator representing a former Confederate state to vote for every significant piece of modern civil rights legislation, Yarborough became a cornerstone of Lyndon Johnson's Great Society programs in the areas of education, environmental preservation, and health care. In doing so, he played a major role in the social and economic modernisation of Texas and the American South. He often defied conventional political wisdom with his stands against powerful political interests and with his vocal opposition to the Vietnam War. To this day, his admirers speak of Yarborough as an inspiration for public service and a model of political independence and integrity. This biography offers the first in-depth look at the life and career of Ralph Yarborough. Patrick L. Cox draws on Yarborough's personal and professional papers, as well as on extensive interviews with the Senator and his associates, to follow Yarborough from his formative years in East Texas through his legal and judicial career in the 1930s, decorated military service in World War II, unsuccessful campaigns for Texas governor in the 1950s, distinguished tenure in the United States Senate from 1957 to 1970, and return to legal practice through the 1980s. Although Yarborough's liberal politics set him at odds with most of the Texas power brokers of his time, including Lyndon Johnson, his accomplishments have become part of the national fabric. Medicare recipients, beneficiaries of the Cold War G. I. Bill, and even beachcombers on Padre Island National Seashore all share in the lasting legacy of Senator Ralph Yarborough. Patrick L. Cox is a historian at the Centre for American History at the University of Texas at Austin.How encounters with strongly electric fish informed our grasp of electricity.Spark from the Deep tells the story of how human beings…
came to understand and use electricity by studying the evolved mechanisms of strongly electric fish. These animals can shock potential prey or would-be predators with high-powered electrical discharges.William J. Turkel asks completely fresh questions about the evolutionary, environmental, and historical aspects of people’s interest in electric fish. Stimulated by painful encounters with electric catfish, torpedos, and electric eels, people learned to harness the power of electric shock for medical therapies and eventually developed technologies to store, transmit, and control electricity. Now we look to these fish as an inspiration for engineering new sensors, computer interfaces, autonomous undersea robots, and energy-efficient batteries.Praise for Spark from the Deep“This beautifully written and exhaustively researched book traces the links between experiments on strongly electric fish and scientific understanding of electricity . . . Turkel’s book is a joy to read; it will entertain and educate scientists, historians, and anyone with an interest in the natural world.” —Choice“Turkel’s book convincingly reminds us that all the laptops and gadgets we surround ourselves with are remixes; altered versions of strongly electric fish. For that strange and insightful observation, this book ought to be widely read and enjoyed.” —Chris Conway, Endeavour“[I]t is refreshing to explore a book which takes seriously ancient encounters with manifestations of natural electricity as precursors to more recent innovations.” —James F. Stark, The British Journal for the History of ScienceLBJ and Vietnam: A Different Kind of War (An Administrative History of the Johnson Presidency)
Par Herring, George C.. 1990
Decades later, the Vietnam War remains a divisive memory for American society. Partisans on all sides still debate why the…
war was fought, how it could have been better fought, and whether it could have been won at all. In this major study, a noted expert on the war brings a needed objectivity to these debates by examining dispassionately how and why President Lyndon Johnson and his administration conducted the war as they did. Drawing on a wealth of newly released documents from the LBJ Library, including the Tom Johnson notes from the influential Tuesday Lunch Group, George Herring discusses the concept of limited war and how it affected President Johnson's decision making, Johnson's relations with his military commanders, the administration's pacification program of 1965-1967, the management of public opinion, and the "fighting while negotiating" strategy pursued after the Tet Offensive in 1968.Seven Wonders of the Universe That You Probably Took for Granted
Par C. Rene James. 2011
A fascinating look at the scientific mysteries behind our everyday world—from night, light and gravity to our cosmic home and…
wonder itself.So much of what surrounds us feels familiar and mundane—until we look closer. C. Renée James opens the Universe to fantastical contemplation in this whimsical tour of seven everyday experiences: night, light, stuff, gravity, time, home, and wonder. James introduces each of these seven wonders with a simple question that appears to be easily answered. The questions are deceptive, though. Although we need light to see, there’s much more to it than meets the eye. When you get down to the atomic level, physical things are made of almost entirely empty space—99.9% nothing. And James’s contemplation of our place in the Universe shows that it’s not just a place to hang your hat—and that there’s really nothing else like it.James’s accessible discussion uses common analogies and entertaining illustrations to explain historical discoveries and concepts such as relativity, antimatter, and the electromagnetic spectrum. Fun and edifying, Seven Wonders of the Universe That You Probably Took for Granted is an inviting introduction to secret knowledge of our everyday world.Perón: A Biography
Par Joseph A. Page. 1983
This biography recounting the Argentinean president&’s rise, fall, and remarkable return to power is &“a formidable achievement&” (Kirkus Reviews, starred…
review). Latin America has produced no more remarkable or enduring political figure than Juan Perón. Born to modest circumstances in 1895 and trained in the military, he rose to power during a period of political uncertainty in Argentina. A shrewd opportunist who understood the needs and aspirations of the country&’s workers, Perón rode their votes to the presidency and then increased their share of the nation&’s wealth. But he also destroyed the independence of their unions and suppressed dissent. Ousted in a coup in 1955, Perón wandered about Latin America and finally settled in Spain, where he masterminded an astonishing political comeback that climaxed in his reelection as president in 1973. Joseph A. Page&’s engrossing biography is based upon interviews, never-before-inspected Argentine and US government documents, and exhaustive research. It spans Perón&’s formative years; his arrest and dramatic rescue by the descamisados in 1945; his relationship with the now mythic Evita; the violence and mysterious murders that punctuated his career; his tragic legacy, personified by his third wife, Isabel, who assumed the presidency after his death under the influence of a Rasputin-like astrologer; and the continuing appeal of Perónism in Argentina. In addition, Page&’s study of Argentine-American relations is particularly penetrating—especially in its description of the struggle between Perón and US ambassador Spruille Braden. &“It would probably take a novel stamped with the surrealistic genius of a Gabriel García Márquez to render all the madness, perverse magic and tragedy of Juan Domingo Perón and his Argentina. But Joseph A. Page has come up with the next best option. . . . A clearly written, definitive study.&” —The New York Times Book Review