Why does time flow inexorably toward the future? A Berkeley physicist proposes that time is expanding because space is expanding.

A simple question from his wife – Does physics really allow people to travel back in time? – propelled Berkeley physicist Richard Muller on a quest to resolve a fundamental problem that had puzzled him throughout his 45-year career: Why does the arrow of time flow inexorably toward the future, constantly creating new “nows”?

In the video, you’ll hear Muller propose a way to test his theory using LIGO. The Laser Interferometer Gravitational-Wave Observatory (LIGO) consists of two widely separated installations within the United States – one in Hanford Washington and the other in Livingston, Louisiana – operated in unison as a single observatory. The LIGO Scientific Collaboration is a group of scientists seeking to make the first direct detection of gravitational waves created by merging black holes, and use them to explore the fundamental physics of gravity.

Bottom line: Video explores the possibility of time travel, and the nature of time and space.

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