Now is a simple conceptyoure reading this sentence now. Yet a real definition of now has eluded even the great Einstein. We know that time stretches and is affected by gravity and velocity. Yet, as eminent physicist Richard A. Muller points out, it is only today that we have all the physics at handrelativity, entropy, entanglement, antimatter, and the Big Bangto explain the flow of time. With these building blocks in place, Muller reaches a startling conclusion: our expanding universe is continuously creating not only new space but also new time. The front edge of this new time is what we call now, and this moment is truly uniqueit is the only moment in which we can exercise our free will. Mullers thought-provoking vision is a powerful counter to established theories in science and philosophy, and his arguments will spark major debate about the most fundamental assumptions of our universe.