The 2018 Physics Today essay competition invites participants to identify a ‘significant advance’ in his or her field since the millennium that deserves wider recognition among non-experts, and to write an essay that describes the advance, how it was made, and why it’s important[1]. This essay takes quantum mechanics to be the field of interest, introducing ‘non-experts’ to a new synthesis of math and physics, of geometry and fields, a computationally precise yet intuitive representation of wavefunctions and their interactions at all scales, allowing for a common sense interpretation of quantum phenomena and resolution of most if not all quantum paradoxes. It’s all about the wavefunction, the foundation, fundamental, quantum philosophy, quantum logic. As yet we are all non-experts.
The 2018 Physics Today essay competition invites participants to identify a ‘significant advance’ in his or her field since the millennium that deserves wider recognition among non-experts, and to write an essay that describes the advance, how it was made, and why it’s important[1]. This essay takes quantum mechanics to be the field of interest, introducing ‘non-experts’ to a new synthesis of math and physics, of geometry and fields, a computationally precise yet intuitive representation of wavefunctions and their interactions at all scales, allowing for a common sense interpretation of quantum phenomena and resolution of most if not all quantum paradoxes. It’s all about the wavefunction, the foundation, fundamental, quantum philosophy, quantum logic. As yet we are all non-experts.
Physics is a vast discipline, rich with topics inviting philosophical analysis. In undertaking that analysis, the philosophy of physics can be pursued in different styles. There is a spectrum: ranging from the ‘theorem-proof’ style as used in expounding a piece of mathematical physics (though here the theorems will be motivated by philosophical ideas), through philosophical-cum-physical argument that adverts in detail to pieces of physics (e.g. in displayed equations), to purely philosophical argument that is in some way based on, or influenced by, physics. For the most part, the essays in this collection are examples of the second of these three styles: they aim to combine detailed presentation of some technicalities in theoretical physics with the dialectical rigour of analytic philosophy. The essays also have, with one exception, a common subject-matter: the philosophy, or if you prefer foundations, of quantum theory. The first six essays fall squarely in that subject-matter. The seventh and eighth broaden the discussion: they address, respectively, philosophical aspects of (i) the search for a theory of quantum gravity, and (ii) quantum theory's use of group theory. The final essay, by Abner Shimony, is much more speculative: it assesses the conjecture that the fundamental laws of nature are products of evolution. Arthur Fine's essay starts the volume, on a central topic in philosophy of quantum theory: proofs of quantum nonlocality. Fine analyses a proof by Lucien Hardy, which as Fine says, is a characteristic example of a new generation of proofs that apparently make less use of probabilities and thereby dispense with inequalities. However, Fine shows that this appearance is misleading.
This novel text directly addresses common claims and misconceptions around quantum mechanics and presents a fresh and modern understanding of this fundamental and essential physical theory. It begins with a non-mathematical introduction to some of the more controversial topics in the foundations of quantum mechanics. For those more familiar with the theoretical framework of quantum mechanics, the text moves on to a general introduction to quantum field theory, followed by a detailed discussion of cutting-edge topics in this area such as decoherence and spontaneous coherence. Several important philosophical problems in quantum mechanics are considered, and their interpretations are compared, notably the Copenhagen and many-worlds interpretations. The inclusion of frequent real-world examples, such as superconductors and superfluids, ensures the book remains grounded in modern research. This book will be a valuable resource for students and researchers in both physics and the philosophy of science interested in the foundations of quantum mechanics.
The universe we live in is both strange and interesting. This strangeness comes about because, at the most fundamental level, the universe is governed by the laws of quantum mechanics. This is the most spectacularly accurate and powerful theory ever devised, one that has given us insights into many aspects of the world, from the structure of matter to the meaning of information. This textbook provides a comprehensive account of all things quantum. It starts by introducing the wavefunction and its interpretation as an ephemeral wave of complex probability, before delving into the mathematical formalism of quantum mechanics and exploring its diverse applications, from atomic physics and scattering, to quantum computing. Designed to be accessible, this volume is suitable for both students and researchers, beginning with the basics before progressing to more advanced topics.
In this magisterial work, Roland Omnès takes us from the academies of ancient Greece to the laboratories of modern science as he seeks to do no less than rebuild the foundations of the philosophy of knowledge. One of the world's leading quantum physicists, Omnès reviews the history and recent development of mathematics, logic, and the physical sciences to show that current work in quantum theory offers new answers to questions that have puzzled philosophers for centuries: Is the world ultimately intelligible? Are all events caused? Do objects have definitive locations? Omnès addresses these profound questions with vigorous arguments and clear, colorful writing, aiming not just to advance scholarship but to enlighten readers with no background in science or philosophy. The book opens with an insightful and sweeping account of the main developments in science and the philosophy of knowledge from the pre-Socratic era to the nineteenth century. Omnès then traces the emergence in modern thought of a fracture between our intuitive, commonsense views of the world and the abstract and--for most people--incomprehensible world portrayed by advanced physics, math, and logic. He argues that the fracture appeared because the insights of Einstein and Bohr, the logical advances of Frege, Russell, and Gödel, and the necessary mathematics of infinity of Cantor and Hilbert cannot be fully expressed by words or images only. Quantum mechanics played an important role in this development, as it seemed to undermine intuitive notions of intelligibility, locality, and causality. However, Omnès argues that common sense and quantum mechanics are not as incompatible as many have thought. In fact, he makes the provocative argument that the "consistent-histories" approach to quantum mechanics, developed over the past fifteen years, places common sense (slightly reappraised and circumscribed) on a firm scientific and philosophical footing for the first time. In doing so, it provides what philosophers have sought through the ages: a sure foundation for human knowledge. Quantum Philosophy is a profound work of contemporary science and philosophy and an eloquent history of the long struggle to understand the nature of the world and of knowledge itself.
Nearing a century since its inception, quantum mechanics is as lively as ever. Its signature manifestations, such as superposition, wave-particle duality, uncertainty principle, entanglement and nonlocality, were long confronted as weird predictions of an incomplete theory, paradoxes only suitable for philosophical discussions, or mere mathematical artifacts with no counterpart in the physical reality. Nevertheless, decades of progress in the experimental verification and control of quantum systems have routinely proven detractors wrong. While fundamental questions still remain wide open on the foundations and interpretations of quantum mechanics, its modern technological applications have captured the fascination of the general public and are having a transformative impact on society. This brief article acts as Introduction to a Special Issue in the Philosophical Transactions of Royal Society A, following from a dedicated Scientific Discussion Meeting where these fascinating topics were explored, giving rise to stimulating debates among speakers and audience. The present issue thus aims at conveying the spirit of those discussions.