Columbia University physicist and mathematician Dr. Brian Greene, author of The Fabric of the Cosmos, joins Art Bell to discuss physics of the universe, time, wormholes, string theory, and parallel universes. Art returns after two weeks spent constructing a massive ham radio antenna in the Nevada desert and opens with wide-ranging commentary on current events, including the Haitian political crisis, a Pentagon climate change report warning of catastrophic weather shifts, and a near-miss asteroid that gave astronomers a nine-hour scare. He also addresses the gay marriage debate at length, sharing his evolving view that no demonstrable harm results from allowing same-sex unions.

Greene explains how Einstein overturned Newton's concept of absolute time, demonstrating that relative motion and gravitational fields cause time to elapse at different rates. He describes how a traveler moving near the speed of light could age one year while thousands of years pass on Earth, a phenomenon confirmed by particle accelerator experiments.

Greene discusses the theoretical possibility of wormholes as tunnels through both space and time, though he expresses skepticism about their practical viability due to energy feedback problems. He addresses string theory, the search for a unified equation describing all fundamental forces, and the idea of parallel universes arising from both quantum mechanics and inflationary cosmology. Greene also shares his view that consciousness is purely physical computation, while acknowledging that science cannot disprove the existence of a divine creator.