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. Though not trying to give a complete answer, this lecture reviews some relevant considerations.

★Tokyo College： https://www.tc.u-tokyo.ac.jp/en/