Quantum Superposition

A clear and engaging discussion Written by a highly respected quantum physicist Puzzling phenomena made comprehensible Describes solutions to challenging quandries in physics

This open access book makes quantum computing more accessible than ever before. A fast-growing field at the intersection of physics and computer science, quantum computing promises to have revolutionary capabilities far surpassing “classical” computation. Getting a grip on the science behind the hype can be tough: at its heart lies quantum mechanics, whose enigmatic concepts can be imposing for the novice. This classroom-tested textbook uses simple language, minimal math, and plenty of examples to explain the three key principles behind quantum computers: superposition, quantum measurement, and entanglement. It then goes on to explain how this quantum world opens up a whole new paradigm of computing. The book bridges the gap between popular science articles and advanced textbooks by making key ideas accessible with just high school physics as a prerequisite. Each unit is broken down into sections labelled by difficulty level, allowing the course to be tailored to the student’s experience of math and abstract reasoning. Problem sets and simulation-based labs of various levels reinforce the concepts described in the text and give the reader hands-on experience running quantum programs. This book can thus be used at the high school level after the AP or IB exams, in an extracurricular club, or as an independent project resource to give students a taste of what quantum computing is really about. At the college level, it can be used as a supplementary text to enhance a variety of courses in science and computing, or as a self-study guide for students who want to get ahead. Additionally, readers in business, finance, or industry will find it a quick and useful primer on the science behind computing’s future.

Named a Best Book of 2021 by the Financial Times and a Best Science Book of 2021 by The Guardian “Rovelli is a genius and an amazing communicator… This is the place where science comes to life.” ―Neil Gaiman “One of the warmest, most elegant and most lucid interpreters to the laity of the dazzling enigmas of his discipline...[a] momentous book” ―John Banville, The Wall Street Journal A startling new look at quantum theory, from the New York Times bestselling author of Seven Brief Lessons on Physics, The Order of Time, and Anaximander. One of the world's most renowned theoretical physicists, Carlo Rovelli has entranced millions of readers with his singular perspective on the cosmos. In Helgoland, he examines the enduring enigma of quantum theory. The quantum world Rovelli describes is as beautiful as it is unnerving. Helgoland is a treeless island in the North Sea where the twenty-three-year-old Werner Heisenberg made the crucial breakthrough for the creation of quantum mechanics, setting off a century of scientific revolution. Full of alarming ideas (ghost waves, distant objects that seem to be magically connected, cats that appear both dead and alive), quantum physics has led to countless discoveries and technological advancements. Today our understanding of the world is based on this theory, yet it is still profoundly mysterious. As scientists and philosophers continue to fiercely debate the meaning of the theory, Rovelli argues that its most unsettling contradictions can be explained by seeing the world as fundamentally made of relationships rather than substances. We and everything around us exist only in our interactions with one another. This bold idea suggests new directions for thinking about the structure of reality and even the nature of consciousness. Rovelli makes learning about quantum mechanics an almost psychedelic experience. Shifting our perspective once again, he takes us on a riveting journey through the universe so we can better comprehend our place in it.

Quantum mechanics is one of the most challenging subjects to learn. It is challenging because quantum phenomenon is counterintuitive, and the mathematics used to explain such a phenomenon is very abstract, and difficult to grasp. This textbook is an attempt to overcome these challenges. Every chapter presents quantum ideas step- by- step in a structured way with a comparison between quantum and classical concepts. It provides a clear distinction between classical and quantum logic. Conceptual questions are provided after every important section so that the reader can test their understanding at every step. Such an approach aids in preventing misconceptions. Problem solving is not restricted to solving differential equations and integration. But it requires to systematically and creatively analyze a problem, to apply the new and powerful concepts for finding a solution and to understand the physical meaning of the solution. The tutorials on special topics are an effort to teach problem solving by actively engaging the reader in a thinking process, to apply the concepts and to understand the physical meaning of the solution. The simulations are provided for some of the topics. The simulations aid in the visualization of the quantum phenomenon, and for meaningful understanding of the mathematics. This approach may lead to development of "quantum mechanical intuition "as well as learning mathematical techniques for problem solving. Most importantly, the book is not flooded with numerous topics that makes the reader confused and distracted, rather the most important topics are discussed at a deeper level. The understanding of quantum mechanics is incomplete without understanding the early ideas and experiments that lead to the development of the quantum theory. Thus, the first two chapters of the book are dedicated to such topics. The key features of this book are: A simplified, structured, and step-by-step introduction to quantum mechanics. The simplification is attained through use of two-level system, step- by- step discussion of important topics in a simplified language at a deeper level, analogies, and visualization using illustrations and simulations A systematic arrangement of topics, and numerous worked- out examples. The presentation of the structure in the mathematical formalism of quantum mechanics provides clarity in understanding complicated and abstract mathematics. It also helps to understand the distinction between the quantum mechanical and classical approaches Conceptual questions at the end of every important section. The conceptual questions can be used in a classroom as a point of discussion between an instructor and students Tutorials on special topics. Simulations on special topics aid in the visualization of the physical phenomenon, and demonstration of the application of mathematics An in-depth discussion of the wave-particle duality, measurement problem, and their philosophical implications in Chapter 2 provides an understanding of the broader meaning of quantum mechanics

Quantum computers are the proposed centerpieces of a revolutionary, 21st century quantum information technology. Ideal for undergraduate and graduate courses in modern quantum physics, Foundations of Quantum Mechanics: From Photons to Quantum Computers takes the reader into the fascinating world of quantum mechanics and continues on an in-depth study of quantum information and quantum computing, including an entire chapter on the future of quantum technology. This accessible text with modern applications focuses on what is “quantum” about quantum mechanics; topics discussed include the EPR paradox, entanglement, teleportation, Bell’s Theorem, quantum computing, and code-breaking with quantum computers.

This book presents the hotly debated question of whether quantum mechanics plays a non-trivial role in biology. In a timely way, it sets out a distinct quantum biology agenda. The burgeoning fields of nanotechnology, biotechnology, quantum technology, and quantum information processing are now strongly converging. The acronym BINS, for Bio-Info-Nano-Systems, has been coined to describe the synergetic interface of these several disciplines. The living cell is an information replicating and processing system that is replete with naturally-evolved nanomachines, which at some level require a quantum mechanical description. As quantum engineering and nanotechnology meet, increasing use will be made of biological structures, or hybrids of biological and fabricated systems, for producing novel devices for information storage and processing and other tasks. An understanding of these systems at a quantum mechanical level will be indispensable. Contents:Foreword (Sir R Penrose)Emergence and Complexity:A Quantum Origin of Life? (P C W Davies)Quantum Mechanics and Emergence (S Lloyd)Quantum Mechanisms in Biology:Quantum Coherence and the Search for the First Replicator (J Al-Khalili & J McFadden)Ultrafast Quantum Dynamics in Photosynthesis (A O Castro, F F Olsen, C F Lee & N F Johnson)Modelling Quantum Decoherence in Biomolecules (J Bothma, J Gilmore & R H McKenzie)The Biological Evidence:Molecular Evolution: A Role for Quantum Mechanics in the Dynamics of Molecular Machines that Read and Write DNA (A Goel)Memory Depends on the Cytoskeleton, but is it Quantum? (A Mershin & D V Nanopoulos)Quantum Metabolism and Allometric Scaling Relations in Biology (L Demetrius)Spectroscopy of the Genetic Code (J D Bashford & P D Jarvis)Towards Understanding the Origin of Genetic Languages (A D Patel)Artificial Quantum Life:Can Arbitrary Quantum Systems Undergo Self-Replication? (A K Pati & S L Braunstein)A Semi-Quantum Version of the Game of Life (A P Flitney & D Abbott)Evolutionary Stability in Quantum Games (A Iqbal & T Cheon)Quantum Transmemetic Intelligence (E W Piotrowski & J S≈adkowski)The Debate:Dreams versus Reality: Plenary Debate Session on Quantum Computing (For Panel: C M Caves, D Lidar, H Brandt, A R Hamilton, Against Panel: D K Ferry, J Gea-Banacloche, S M Bezrukov, L B Kish, Debate Chair: C R Doering, Transcript Editor: D Abbott)Plenary Debate: Quantum Effects in Biology: Trivial or Not? (For Panel: P C W Davies, S Hameroff, A Zeilinger, D Abbott, Against Panel: J Eisert, H M Wiseman, S M Bezrukov, H Frauenfelder, Debate Chair: J Gea-Banacloche, Transcript Editor: D Abbott)Nontrivial Quantum Effects in Biology: A Skeptical Physicist's View (H Wiseman & J Eisert)That's Life! — The Geometry of π Electron Clouds (S Hameroff) Readership: Graduate students and researchers in quantum physics, biophysics, nanosciences, quantum chemistry, mathematical biology and complexity theory, as well as philosophers of science. Keywords:Quantum Biology;Quantum Computation;Quantum Mechanics;Biophysics;Nanotechnology;Quantum Technology;Quantum Information Processing;Bio-Info-Nano-Systems (BINS);Emergence;Complexity;Complex Systems;Cellular Automata;Game Theory;Biomolecules;Photosynthesis;DNA;Genetic Code;DecoherenceKey Features:Is structured in a debate style, where contributors argue opposing positionsBrings together some of the finest minds and latest developments in the fieldIs entirely unique and there are no competing titles

Steven French suggests a radical new approach to the understanding of quantum physics, derived from Husserl's phenomenological philosophy. In 1939 two physicists, Fritz London and Edmund Bauer, published an account of measurement in quantum mechanics. Widely cited, their 'little book' featured centrally in an important debate over the role of consciousness in that process. However, it has been fundamentally misunderstood, both in that debate and beyond. Steven French argues that London, in particular, approached the measurement process from the perspective of Husserlian phenomenology, which he had studied as a student and which he retained an interest in throughout his career. This casts his work with Bauer in an entirely novel light and suggests a radical alternative understanding of quantum mechanics in which consciousness still plays a role but one that is fundamentally different than previously conceived. Most interpretations of the theory approach it on the basis of the so-called 'analytic' tradition in philosophy. However, there has recently been a surge of interest in 'continental' approaches and this book offers a significant new contribution to such developments. Intertwining history and philosophy, it presents London's background in physics and phenomenology, together with an outline of the latter as developed by Husserl, Gurwitsch, Merleau-Ponty, and others, as well as a detailed analysis of the work on measurement with Bauer. The book concludes by comparing the London and Bauer understanding with that afforded by Fuch's QBism, Everett's 'Many Worlds' interpretation, and Rovelli's Relational Quantum Mechanics. It is hoped that this exploratory work will open up new avenues of thought with regard to one of our most fundamental physical theories.

Quantum mechanics was developed during the first few decades of the twentieth century via a series of inspired guesses made by various physicists, including Planck, Einstein, Bohr, Schroedinger, Heisenberg, Pauli, and Dirac. All these scientists were trying to construct a self-consistent theory of microscopic dynamics that was compatible with experimental observations. The purpose of this book is to present quantum mechanics in a clear, concise, and systematic fashion, starting from the fundamental postulates, and developing the theory in as logical a manner as possible. Topics covered in the book include the fundamental postulates of quantum mechanics, angular momentum, time-independent and time-dependent perturbation theory, scattering theory, identical particles, and relativistic electron theory.