The Many Worlds of Hugh Everett III

Author: Peter Byrne
Publisher: OUP Oxford
ISBN: 9780191655227
Release Date: 2012-12-13
Genre: Science

Peter Byrne tells the story of Hugh Everett III (1930-1982), whose "many worlds" theory of multiple universes has had a profound impact on physics and philosophy. Using Everett's unpublished papers (recently discovered in his son's basement) and dozens of interviews with his friends, colleagues, and surviving family members, Byrne paints, for the general reader, a detailed portrait of the genius who invented an astonishing way of describing our complex universe from the inside. Everett's mathematical model (called the "universal wave function") treats all possible events as "equally real", and concludes that countless copies of every person and thing exist in all possible configurations spread over an infinity of universes: many worlds. Afflicted by depression and addictions, Everett strove to bring rational order to the professional realms in which he played historically significant roles. In addition to his famous interpretation of quantum mechanics, Everett wrote a classic paper in game theory; created computer algorithms that revolutionized military operations research; and performed pioneering work in artificial intelligence for top secret government projects. He wrote the original software for targeting cities in a nuclear hot war; and he was one of the first scientists to recognize the danger of nuclear winter. As a Cold Warrior, he designed logical systems that modeled "rational" human and machine behaviors, and yet he was largely oblivious to the emotional damage his irrational personal behavior inflicted upon his family, lovers, and business partners. He died young, but left behind a fascinating record of his life, including correspondence with such philosophically inclined physicists as Niels Bohr, Norbert Wiener, and John Wheeler. These remarkable letters illuminate the long and often bitter struggle to explain the paradox of measurement at the heart of quantum physics. In recent years, Everett's solution to this mysterious problem - the existence of a universe of universes - has gained considerable traction in scientific circles, not as science fiction, but as an explanation of physical reality.

The Quantum Labyrinth

Author: Paul Halpern
Publisher: Hachette UK
ISBN: 9780465097593
Release Date: 2017-10-17
Genre: Science

The story of the unlikely friendship between the two physicists who fundamentally recast the notion of time and history In 1939, Richard Feynman, a brilliant graduate of MIT, arrived in John Wheeler's Princeton office to report for duty as his teaching assistant. A lifelong friendship and enormously productive collaboration was born, despite sharp differences in personality. The soft-spoken Wheeler, though conservative in appearance, was a raging nonconformist full of wild ideas about the universe. The boisterous Feynman was a cautious physicist who believed only what could be tested. Yet they were complementary spirits. Their collaboration led to a complete rethinking of the nature of time and reality. It enabled Feynman to show how quantum reality is a combination of alternative, contradictory possibilities, and inspired Wheeler to develop his landmark concept of wormholes, portals to the future and past. Together, Feynman and Wheeler made sure that quantum physics would never be the same again.

Photons in Fock Space and Beyond

Author: Reinhard Honegger
Publisher: World Scientific
ISBN: 9789814618854
Release Date: 2015-04-22
Genre: Science

The three-volume major reference “Photons in Fock Space and Beyond” undertakes a new mathematical and conceptual foundation of the theory of light emphasizing mesoscopic radiation systems. The quantum optical notions are generalized beyond Fock representations where the richness of an infinite dimensional quantum field system, with its mathematical difficulties and theoretical possibilities, is fully taken into account. It aims at a microscopic formulation of a mesoscopic model class which covers in principle all stages of the generation and propagation of light within a unified and well-defined conceptual frame. The dynamics of the interacting systems is founded — according to original works of the authors — on convergent perturbation series and describes the developments of the quantized microscopic as well as the classical collective degrees of freedom at the same time. The achieved theoretical unification fits especially to laser and microwave applications inheriting objective information over quantum noise. A special advancement is the incorporation of arbitrary multiply connected cavities where ideal conductor boundary conditions are imposed. From there arises a new category of classical and quantized field parts, apparently not treated in Quantum Electrodynamics before. In combination with gauge theory, the additional “cohomological fields” explain topological quantum effects in superconductivity. Further applications are to be expected for optoelectronic and optomechanical systems. Contents:Volume I: From Classical to Quantized Radiation Systems:Preliminaries on ElectromagnetismClassical Electrodynamics in L2-Hilbert SpacesClassical Electrodynamics in the Smeared Field FormalismStatistical Classical ElectrodynamicsCanonical Quantization and Weyl AlgebrasDeformation QuantizationOptical States, Optical CoherenceVolume II: Quantized Mesoscopic Radiation Models:SqueezingBlack Body RadiationMesoscopic Electronic Matter Algebras and StatesWeakly Inhomogeneous InteractionsQuantized Radiation ModelsVolume III: Mathematics for Photon Fields:Observables and AlgebrasStates and Their Decomposition MeasuresDynamics and Perturbation TheoryGauges and Fiber Bundles Readership: This three-volume series is recommended for graduate students and researchers working in rigorous Electrodynamics, Quantum Optics and Quantum Field Theory in general. Key Features:On the side of Physics, “Photons in Fock Space and Beyond” extends the applicability of quantum optical notions far beyond the usual scope of the quantum optical literature by using more general optical cavities and theoretical ansatzes. By establishing a systematic conceptual frame, many fundamental questions of photon theory are clarified by mathematical argumentsOn the side of Mathematical Physics, certain parts of the theory of vector fields with boundary conditions, of operator algebras, ergodic theory, convexity, measures on dual spaces, perturbation theory and electrodynamic gauge bundles are not only treated in an introductory fashion but also supplemented in an original mannerThe unique feature of that exposition of mathematical disciplines is their integration into a comprehesive line of thought within a deductive physical theoryKeywords:Electrodynamics;Vector Analysis;Statistical Physics;Quantum Optics;Quantum Field Theory;Quantum Statistics;Solid State Physics;Superconductivity;Gauge Theory;Operator Algebras;Convexity;Topological Vector Spaces;Fiber BundlesReviews: “This three volume work on the quantum field theory of radiation combines well presented, competent mathematical foundations with actual physical applications to mesoscopic photonics.” (See Full Review) Professor Ernst Binz Universität Mannheim

Many Worlds

Author: Simon Saunders
Publisher: Oxford University Press
ISBN: 9780199560561
Release Date: 2010-06-24
Genre: Philosophy

What would it mean to apply quantum theory, without restriction and without involving any notion of measurement and state reduction, to the whole universe? What would realism about the quantum state then imply?This book brings together an illustrious team of philosophers and physicists to debate these questions. The contributors broadly agree on the need, or aspiration, for a realist theory that unites micro- and macro-worlds. But they disagree on what this implies. Some argue that if unitary quantum evolution has unrestricted application, and if the quantum state is taken to be something physically real, then this universe emerges from the quantum state as one of countless others, constantlybranching in time, all of which are real. The result, they argue, is many worlds quantum theory, also known as the Everett interpretation of quantum mechanics. No other realist interpretation of unitary quantum theory has ever been found.Others argue in reply that this picture of many worlds is in no sense inherent to quantum theory, or fails to make physical sense, or is scientifically inadequate. The stuff of these worlds, what they are made of, is never adequately explained, nor are the worlds precisely defined; ordinary ideas about time and identity over time are compromised; no satisfactory role or substitute for probability can be found in many worlds theories; they can't explain experimental data; anyway, there areattractive realist alternatives to many worlds.Twenty original essays, accompanied by commentaries and discussions, examine these claims and counterclaims in depth. They consider questions of ontology - the existence of worlds; probability - whether and how probability can be related to the branching structure of the quantum state; alternatives to many worlds - whether there are one-world realist interpretations of quantum theory that leave quantum dynamics unchanged; and open questions even given many worlds, including the multiverseconcept as it has arisen elsewhere in modern cosmology. A comprehensive introduction lays out the main arguments of the book, which provides a state-of-the-art guide to many worlds quantum theory and its problems.