Time seems natural and absolute: the flow of moments, one following another, from the unknown past to the knife's edge present to the unknowable future. But perhaps this is not so. Einstein shocked the world by showing that time was relative. What's the latest about time?

Free access to Closer to Truth's library of 5,000 videos: http://bit.ly/376lkKN

Watch more interviews on time: https://bit.ly/34b9sZ5

David Jonathan Gross is an American particle physicist and string theorist.

Register for free at CTT.com for subscriber-only exclusives: http://bit.ly/2GXmFsP

Closer to Truth presents the world’s greatest thinkers exploring humanity’s deepest questions. Discover fundamental issues of existence. Engage new and diverse ways of thinking. Appreciate intense debates. Share your own opinions. Seek your own answers.