The physical interpretation of quantum mechanics has been a controversial riddle since the 1920s, when Niels Bohr argued that the atom's inner workings could not be described in physical terms. Today, many philosophers and physicists disagree, but there's no consensus on an alternative. Philosopher David Albert's provocative book argues, in three essays, that Bohr's quantum-measurement problem starts to make sense if the wave function is understood as the fundamental physical 'stuff' of the Universe.--Andrew Robinson, Nature A deep, and deeply important, contribution to the metaphysics of physics, and indeed to metaphysics more generally. It deserves careful and sustained attention.--David Wallace, Mind Albert has proven himself time and again to be a visionary who faces these old puzzles without flinching. I hope, in another half-decade, to read his next book.--David Kordahl, 3 Quarks Daily An enormously significant contribution to the philosophy of physics and to metaphysics more generally.

In his usual charming and deceptively easy-to-follow style, Albert proposes a novel account of the relation between the fundamental and the non-fundamental--one of the central issues in metaphysics. This is sure to generate a great deal of discussion in the field.--Barry Loewer, Distinguished Professor of Philosophy, Rutgers University A must-read for anyone interested in the philosophy of physics or adjacent portions of metaphysics. Wave-function realism's offensive is advanced, its defenses bolstered, its intuitive core reimagined. Insightful and deep and challenging and (of course) fun--vintage Albert.--Theodore Sider, author of The Tools of Metaphysics and the Metaphysics of Science Albert presents a strikingly original picture of the structure of quantum mechanics and how it describes the world. He shows, by construction, what it is that unifies approaches like the Ghirardi-Rimini-Weber theory, Bohmian mechanics, and the many-worlds formulations. For those who understand the quantum measurement problem and have begun to think carefully about how to solve it, this is an essential read.

--Jeffrey Barrett, author of The Conceptual Foundations of Quantum Mechanics For a quarter of a century, David Albert has been one of the chief advocates of the wave-function-realist interpretation of quantum mechanics. In this beautifully written and provocative new book, Albert presents the case, as he sees it, for wave-function realism and its surprising higher-dimensional metaphysical framework.--Alyssa Ney, author of The World in the Wave Function: A Metaphysics for Quantum Physics Quantum-mechanical phenomena prove that somehow or other classical physics--and even 'common sense'--have led us massively astray about the fundamental structure of the world. Albert, in his inimitable conversational style, digs deeply into the argument that our intuitive notion of the structure of physical space lies at the root of the problem.--Tim Maudlin, author of Philosophy of Physics: Quantum Theory.