TIME REBORN

A distinguished physicist delivers a thoughtful, complex re-evaluation of the role of time in the universe.

Smolin (The Trouble with Physics: The Rise of String Theory, the Fall of a Science, and What Comes Next, 2006) points out that no one doubts that space is real. If the cosmos were empty, space would exist, but there would be no time. So time is inextricably bound up with the material universe, a real phenomenon at the heart of nature. This turns out to be controversial since the great thinkers from Plato to Newton to Einstein taught that time is an illusion that humans must transcend to achieve true understanding. Smolin disagrees, maintaining that embracing its reality is the key to solving the great problems in physics. He makes a case that Newton’s paradigm—knowing the forces acting on any system allows us, following natural laws, to predict its future state—is a fallacy. It works for limited areas and short periods but fails on universal scales. In fact, natural laws themselves are less immutable than time. For a straightforward popular introduction to time, read Sean Carroll’s From Eternity to Here (2010). Smolin has bigger fish to fry as he muses over great issues in his field as they relate to time, such as the stubborn refusal of relativity to mesh with quantum theory, pausing regularly for detours into cosmology, economics and climate change.

This is a work as much of philosophy as science. Despite the absence of mathematics, it requires close attention, but readers who make the effort will absorb a flood of ideas from an imaginative thinker.