Quantum physics has been, ever since its inception, the golden child of science. It is the basis of our understanding of everything from elemental particles to the behaviour of materials. Yet is has also been a troubled child, beset by controversy and raging disagreement over which formulation best describes our world. It has helped physicists agree that atoms and radiation behave differently to rocks and cats, but often not on much else. The simple reason quantum physics is unsolvable, Lee Smolin argues, is that the theory is incomplete. In this radical new theory of reality, he aims to go beyond quantum mechanics to find a description of the world that makes sense to everyone: an alternative theory, based on the one that nature uses. In doing so, he takes away the mystery and confusion, and presents the quantum world in a way that is accessible to all – specialist and non-specialist.