Saturday, November 28, 2009

Why Can't Time Run Backwards?

Nobel Laureate Tony Leggett gave a rather intriguing lecture at St. Andrews this week that tried to address the topic.

Leggett said, "We can all tell when a movie of some everyday event, such as a kettle boiling or a glass shattering, is run backwards.

"Similarly, we all feel that we can remember the past and affect the future, not vice versa. So there is a very clear "arrow" ( direction ) of time built into our interpretation of our everyday experience.

"Yet the fundamental microscopic laws of physics, be they classical or quantum-mechanical, look exactly the same if the direction of time is reversed. So what is the origin of the "arrow" of time?

"This is one of the deepest questions in physics; I will review some relevant considerations, but do not pretend to give a complete answer."


It took place on Nov. 27 (yesterday). Did anyone reading this attended this lecture? If you did, I'd appreciate a brief report.

Zz.

1 comment:

John said...

The lecture seemed ot me a fairly general overview of the concept of time and its directionality. It was interesting, ideal for an interested sixth former or undergraduate. However, I didn't think there was much that I didn't know before.

John