Now: The Physics of Time

Muller (Physics for Future Presidents), professor of physics at the UC Berkeley, looks anew at the physics of time in this provocative book. Scientists have puzzled over a definition of now for centuries. Einstein’s relativity theory showed that time is dependent on the observer’s frame of reference, but the news that the speed of light is constant for all observers also removed any hopes of the existence of universal simultaneity. Even more intriguing, relativity showed that time actually slows for moving objects, giving life to a host of paradoxes. Muller addresses the largest question—can the “arrow” of time go forward only?—by giving readers a closer look at the nature of entropy and how it has increased since the Big Bang. But the discovery of the Higgs boson opened up the possibility that entropy isn’t driving the forward march of time. Quantum physics may yet yield a “quantum arrow” to time, Muller says, based by work by Richard Feynman and others. With a little help from such pop culture touchstones as Star Trek, Jurassic Park, and Calvin and Hobbes, Muller delivers an intriguing glimpse at the physics behind time. (Sept.)