Hugh Everett III was an American physicist best known for his many-worlds interpretation of quantum mechanics, which formed the basis of his PhD thesis at Princeton University in 1957. Although counterintuitive, Everett's revolutionary formulation of quantum mechanics offers the most direct solution to the infamous quantum measurement problem--that is, how and why the singular world of our experience emerges from the multiplicities of alternatives available in the quantum world. The many-worlds interpretation postulates the existence of multiple universes. Whenever a measurement-like interaction occurs, the universe branches into relative states, one for each possible outcome of the measurement, and the world in which we find ourselves is but one of these many, but equally real, possibilities. Everett's challenge to the orthodox interpretation of quantum mechanics was met with scorn from Niels Bohr and other leading physicists, and Everett subsequently abandoned academia to conduct military operations research. Today, however, Everett's formulation of quantum mechanics is widely recognized as one of the most controversial but promising physical theories of the last century. In this book, Jeffrey Barrett and Peter Byrne present the long and short versions of Everett's thesis along with a collection of his explanatory writings and correspondence. These primary source documents, many of them newly discovered and most unpublished until now, reveal how Everett's thinking evolved from his days as a graduate student to his untimely death in 1982. This definitive volume also features Barrett and Byrne's introductory essays, notes, and commentary that put Everett's extraordinary theory into historical and scientific perspective and discuss the puzzles that still remain.
Hugh Everett III was an American physicist best known for his many-worlds interpretation of quantum mechanics, which formed the basis of his PhD thesis at Princeton University in 1957. Although counterintuitive, Everett's revolutionary formulation of quantum mechanics offers the most direct solution to the infamous quantum measurement problem--that is, how and why the singular world of our experience emerges from the multiplicities of alternatives available in the quantum world. The many-worlds interpretation postulates the existence of multiple universes. Whenever a measurement-like interaction occurs, the universe branches into relative states, one for each possible outcome of the measurement, and the world in which we find ourselves is but one of these many, but equally real, possibilities. Everett's challenge to the orthodox interpretation of quantum mechanics was met with scorn from Niels Bohr and other leading physicists, and Everett subsequently abandoned academia to conduct military operations research. Today, however, Everett's formulation of quantum mechanics is widely recognized as one of the most controversial but promising physical theories of the last century. In this book, Jeffrey Barrett and Peter Byrne present the long and short versions of Everett's thesis along with a collection of his explanatory writings and correspondence. These primary source documents, many of them newly discovered and most unpublished until now, reveal how Everett's thinking evolved from his days as a graduate student to his untimely death in 1982. This definitive volume also features Barrett and Byrne's introductory essays, notes, and commentary that put Everett's extraordinary theory into historical and scientific perspective and discuss the puzzles that still remain.
Hugh Everett III was an American physicist best known for his many-worlds interpretation of quantum mechanics, which formed the basis of his PhD thesis at Princeton University in 1957. Although counterintuitive, Everett's revolutionary formulation of quantum mechanics offers the most direct solution to the infamous quantum measurement problem--that is, how and why the singular world of our experience emerges from the multiplicities of alternatives available in the quantum world. The many-worlds interpretation postulates the existence of multiple universes. Whenever a measurement-like interaction occurs, the universe branches into relative states, one for each possible outcome of the measurement, and the world in which we find ourselves is but one of these many, but equally real, possibilities. Everett's challenge to the orthodox interpretation of quantum mechanics was met with scorn from Niels Bohr and other leading physicists, and Everett subsequently abandoned academia to conduct military operations research. Today, however, Everett's formulation of quantum mechanics is widely recognized as one of the most controversial but promising physical theories of the last century.
In this book, Jeffrey Barrett and Peter Byrne present the long and short versions of Everett's thesis along with a collection of his explanatory writings and correspondence. These primary source documents, many of them newly discovered and most unpublished until now, reveal how Everett's thinking evolved from his days as a graduate student to his untimely death in 1982. This definitive volume also features Barrett and Byrne's introductory essays, notes, and commentary that put Everett's extraordinary theory into historical and scientific perspective and discuss the puzzles that still remain.
In April of 1956, Hugh Everett III’s draft doctoral thesis, tentatively titled “Wave Mechanics without Probability”, was circulated by his thesis advisor at Princeton University John Wheeler to several leading physicists in the West, including the godfather of quantum mechanics Niels Bohr. Everett aimed at resolving the measurement problem in quantum mechanics. Everett’s solution to the mystery of how, when, where and why the wave function collapses in the measurement process was straightforward: it does not. Due to the opposition of Bohr and other adherents to the Copenhagen Interpretation of quantum mechanics, an objection by Feynman and Wheeler’s growing ambivalence, Everett was required to abridge his thesis, resulting in the publication of “’Relative State’ Formulation of Quantum Mechanics” in July 1957. Everett’s machinery of interpretation, including his information and measure theoretic interpretation of the wave function, his concept of correlation within the superposition, as well as his philosophy of science which provides important context for his theory, are largely absent from the latter “Short Thesis”. Perhaps due to the unusual publication history of his works, many critics of Everett and even many of his supporters have overlooked the significance of the arguments made in the “Long Thesis”, which was published only in 1973. Everett’s fuller exposition there answers often cited criticisms such as Adrian Kent’s “Against Many Worlds Interpretations”. Other popular misconceptions about Everett, that he was driven out of academia or that his thesis was redacted due solely or primarily to the opposition from Copenhagen, do not stand up to careful scrutiny of the historical evidence.
The Many-worlds Interpretation (MWI) of quantum mechanics has captivated physicists and philosophers alike since its inception in the mid-20th century. This paper explores the historical roots, evolution, and implications of the MWI within the context of quantum theory. Beginning with an overview of early developments in quantum mechanics and the emergence of foundational interpretations, we delve into the origins of the MWI through the groundbreaking work of physicist Hugh Everett III. Everett's doctoral thesis proposed a radical solution to the measurement problem, positing the existence of multiple branching universes to account for quantum phenomenon. We trace the evolution of the MWI, examining its refinement and elaboration by subsequent physicists such as John Wheeler. Furthermore, we discuss the MWI's impact on contemporary physics, including its connections to quantum information theory and ongoing experimental tests. By providing a comprehensive analysis of the MWI's historical development and current relevance, this paper offers insights into one of the most provocative interpretations of quantum mechanics and its implications for our understanding of the universe.
A novel interpretation of quantum mechanics, first proposed in brief form by Hugh Everett in 1957, forms the nucleus around which this book has developed. In his interpretation, Dr. Everett denies the existence of a separate classical realm and asserts the propriety of considering a state vector for the whole universe. Because this state vector never collapses, reality as a whole is rigorously deterministic. This reality, which is described jointly by the dynamical variables and the state vector, is not the reality customarily perceived; rather, it is a reality composed of many worlds. By virtue of the temporal development of the dynamical variables, the state vector decomposes naturally into orthogonal vectors, reflecting a continual splitting of the universe into a multitude of mutually unobservable but equally real worlds, in each of which every good measurement has yielded a definite result, and in most of which the familiar statistical quantum laws hold. The volume contains Dr. Everett's short paper from 1957, "'Relative State' Formulation of Quantum Mechanics," and a far longer exposition of his interpretation, entitled "The Theory of the Universal Wave Function," never before published. In addition, other papers by Wheeler, DeWitt, Graham, and Cooper and Van Vechten provide further discussion of the same theme. Together, they constitute virtually the entire world output of scholarly commentary on the Everett interpretation. Originally published in 1973. The Princeton Legacy Library uses the latest print-on-demand technology to again make available previously out-of-print books from the distinguished backlist of Princeton University Press. These editions preserve the original texts of these important books while presenting them in durable paperback and hardcover editions. The goal of the Princeton Legacy Library is to vastly increase access to the rich scholarly heritage found in the thousands of books published by Princeton University Press since its founding in 1905.
Recent years have seen a good deal of work done on one of the most mind blowing and conceptually radical views in quantum mechanics, namely the ‘many worlds’ interpretation of quantum mechanics. Many worlds was first proposed by Hugh Everett III in his long Ph.D. dissertation, which only some years later, and after significant shortening, came to be published as the ‘Relative State Formulation of Quantum Mechanics’ (Everett 1957). To commemorate the 50th anniversary of the first publication of Everett's ideas, two conferences were held at Oxford University and the Perimeter Institute, which brought together some of the most active researchers in the field. The works presented in these two conferences have now been compiled in the volume Many Worlds? Everett, Quantum Theory and Reality, edited by Simon Saunders, Jonathan Barrett, Adrian Kent and David Wallace.1 This is then a comprehensive collection of papers – 23 papers altogether – where the reader will find virtually anything that can be said about the many worlds interpretation today.