Abstract

Most people would probably agree that the obvious feature about time is that it progresses (or flows). However, our everyday experience of the apparent ‘dynamic’ nature of time conflicts with the basic laws of physics which do not posit any passage of time. This clash between experience and fundamental physics has led a few physicists to develop theories of the universe in which time’s passage is an explicit feature. Two such theories are discussed along with a possible non-‘dynamic’ alternative.