Quantum theory attempts to describe the discrete or atomic nature of matter and the physical world. Certain paradoxes connected with the use of our familiar ideas of the theory have led some physicists to suggest that a revision of quantum theory at its most fundamental level is now inevitable, while others think that the wide range of experimental success of the theory make such changes literally unthinkable. This book contains the edited papers presented at a small informal colloquium held in Cambridge in 1968 to discuss the need for fundamental revision in quantum theory. Most schools of thought on the foundations of the theory were represented, and to direct discussion some participants proposed actual changes. A principal aim was to pinpoint the source of difficulty in current ideas of the time or, failing that, to present alongside each other the various viewpoints about them.

This clearly explained layman's introduction to quantum physics is an accessible excursion into metaphysics and the meaning of reality. Herbert exposes the quantum world and the scientific and philosophical controversy about its interpretation.

“Anyone who is not shocked by quantum theory has not understood it.” Since Niels Bohr said this many years ago, quantum mechanics has only been getting more shocking. We now realize that it’s not really telling us that “weird” things happen out of sight, on the tiniest level, in the atomic world: rather, everything is quantum. But if quantum mechanics is correct, what seems obvious and right in our everyday world is built on foundations that don’t seem obvious or right at all—or even possible. An exhilarating tour of the contemporary quantum landscape, Beyond Weird is a book about what quantum physics really means—and what it doesn’t. Science writer Philip Ball offers an up-to-date, accessible account of the quest to come to grips with the most fundamental theory of physical reality, and to explain how its counterintuitive principles underpin the world we experience. Over the past decade it has become clear that quantum physics is less a theory about particles and waves, uncertainty and fuzziness, than a theory about information and knowledge—about what can be known, and how we can know it. Discoveries and experiments over the past few decades have called into question the meanings and limits of space and time, cause and effect, and, ultimately, of knowledge itself. The quantum world Ball shows us isn’t a different world. It is our world, and if anything deserves to be called “weird,” it’s us.

Presents the problems of quantum theory from the perspective of mathematical formalism. -- Back cover.

The present wave of interest in quantum foundations is caused by the tremendous development of quantum information science and its applications to quantum computing and quantum communication. It has become clear that some of the difficulties encountered in realizations of quantum information processing have roots at the very fundamental level. To solve such problems, quantum theory has to be reconsidered. This book is devoted to the analysis of the probabilistic structure of quantum theory, probing the limits of classical probabilistic representation of quantum phenomena.

One of Smithsonian's Favorite Books of 2018 One of Forbes's 2018 Best Books About Astronomy, Physics and Mathematics One of Kirkus's Best Books of 2018 The intellectual adventure story of the "double-slit" experiment, showing how a sunbeam split into two paths first challenged our understanding of light and then the nature of reality itself--and continues to almost 200 years later. Many of science's greatest minds have grappled with the simple yet elusive "double-slit" experiment. Thomas Young devised it in the early 1800s to show that light behaves like a wave, and in doing so opposed Isaac Newton. Nearly a century later, Albert Einstein showed that light comes in quanta, or particles, and the experiment became key to a fierce debate between Einstein and Niels Bohr over the nature of reality. Richard Feynman held that the double slit embodies the central mystery of the quantum world. Decade after decade, hypothesis after hypothesis, scientists have returned to this ingenious experiment to help them answer deeper and deeper questions about the fabric of the universe. How can a single particle behave both like a particle and a wave? Does a particle exist before we look at it, or does the very act of looking create reality? Are there hidden aspects to reality missing from the orthodox view of quantum physics? Is there a place where the quantum world ends and the familiar classical world of our daily lives begins, and if so, can we find it? And if there's no such place, then does the universe split into two each time a particle goes through the double slit? With his extraordinarily gifted eloquence, Anil Ananthaswamy travels around the world and through history, down to the smallest scales of physical reality we have yet fathomed. Through Two Doors at Once is the most fantastic voyage you can take.

"From the electron microscope to the Hubble space telescope, modern technological advances have broadened our horizons - macroscopic and microscopic - beyond anything imaginable prior to the 1930s. One of the most important discoveries of the past few decades is the fact that everything, beginning with subatomic particles and including star systems and conscious human life, emerges from an underlying, transcendent Reality that brings all things from nonexistence into being through a continuous act of creation. All things are essentially interconnected in an entangled unity, which obliges us to view the world as a great hologram in which every aspect contains information of the Whole. This book raises the question of the relationship between that Reality and the Christian understanding of God. Written in the form of a simple novel, it begins by offering an overview, in lay terms, of quantum theory as it has developed since the early twentieth century. Gradually it lays the groundwork for an exploration of the relationship between quantum mechanics and certain key aspects of traditional Christian teaching. Its aim is to make clear that our usual conception of God and the world, in the words of the English theologian J.B. Phillips, is far 'too small.' With the help of insights drawn from quantum theory, we can now see that Creation is more intricate, more interconnected and more beautiful than our forebears could ever have imagined."--Publisher.

Already Einstein could never see quantum mechanics as a complete theory. Nowadays, many researchers, including 't Hooft, view quantum mechanics as a statistical description of some underlying reality. The workshop Beyond the Quantum, organized in Spring 2006 at the Lorentz Center in Leiden, The Netherlands, was one of the first meetings completely devoted to physics that may need an explanation beyond quantum mechanics. A broad variety of subjects was covered. The present book reflects this. Sample Chapter(s). Chapter 1: The Mathematical Basis for Deterministic Quantum Mechanics (267 KB). Contents: Introductions: The Mathematical Basis for Deterministic Quantum Mechanics (G 't Hooft); What Did We Learn from Quantum Gravity? (A Ashtekar); BoseOCoEinstein Condensates and EPR Quantum Non-Locality (F Lalo1/2); The Quantum Measurement Process: Lessons from an Exactly Solvable Model (A E Allahverdyan et al.); Quantum Mechanics and Quantum Information: POVMs: A Small but Important Step Beyond Standard Quantum Mechanics (W M de Muynck); State Reduction by Measurements with a Null Result (G Nienhuis); Solving Open Questions in the BoseOCoEinstein Condensation of an Ideal Gas via a Hybrid Mixture of Laser and Statistical Physics (M Kim et al.); Long Distance Correlations and Bell Inequalities: Fair Sampling vs No-Signalling Principle in EPR Experiments (G Adenier & A Yu Khrennikov); Mathematical Foundations: Where the Mathematical Structure of Quantum Mechanics Comes From (G M D'Ariano); Phase Space Description of Quantum Mechanics and Non-Commutative Geometry: Wigner-Moyal and Bohm in a Wider Context (B J Hiley); Quantum Mechanics as Simple Algorithm for Approximation of Classical Integrals (A Yu Khrennikov); Stochastic Electrodynamics: Some Quantum Experiments from the Point of View of Stochastic Electrodynamics (V apicka et al.); Models for the Electron: Rotating Hopf-Kinks: Oscillators in the Sense of de Broglie (U Enz); The Electron and the Neutrino as Solitos in Classical Electromagnetism (Th M Nieuwenhuizen); Philosophical Considerations; Round Table; and other papers. Readership: Postgraduates and researchers in quantum physics."

A daring new vision of the quantum universe, and the scandals controversies, and questions that may illuminate our future--from Canada's leading mind on contemporary physics. Quantum physics is the golden child of modern science. It is the basis of our understanding of atoms, radiation, and so much else, from elementary particles and basic forces to the behaviour of materials. But for a century it has also been the problem child of science, plagued by intense disagreements between its intellectual giants, from Albert Einstein to Stephen Hawking, over the strange paradoxes and implications that seem like the stuff of fantasy. Whether it's Schrödinger's cat--a creature that is simultaneously dead and alive--or a belief that the world does not exist independently of our observations of it, quantum theory is what challenges our fundamental assumptions about our reality. In Einstein's Unfinished Revolution, globally renowned theoretical physicist Lee Smolin provocatively argues that the problems which have bedeviled quantum physics since its inception are unsolved for the simple reason that the theory is incomplete. There is more, waiting to be discovered. Our task--if we are to have simple answers to our simple questions about the universe we live in--must be to go beyond it to a description of the world on an atomic scale that makes sense. In this vibrant and accessible book, Smolin takes us on a journey through the basics of quantum physics, introducing the stories of the experiments and figures that have transformed the field, before wrestling with the puzzles and conundrums that they present. Along the way, he illuminates the existing theories about the quantum world that might solve these problems, guiding us toward his own vision that embraces common sense realism. If we are to have any hope of completing the revolution that Einstein began nearly a century ago, we must go beyond quantum mechanics as we know it to find a theory that will give us a complete description of nature. In Einstein's Unfinished Revolution, Lee Smolin brings us a step closer to resolving one of the greatest scientific controversies of our age.