Time is real – if you view it through the lens of heat

The way most people think about time is wrong. The notion that we share a ‘common time’ moving in a single direction is a useful illusion but, as physicists have understood since the discoveries of Albert Einstein, it doesn’t comport with our understanding of the Universe. However, as the Italian theoretical physicist and writer Carlo Rovelli argues in this short documentary from Quanta Magazine, this doesn’t mean we should abandon the concept of time altogether. Instead, we should recognise that ‘many possible times’ coexist. Rovelli further proposes that the best way to understand how time actually works is through the lens of entropy and, by extension, heat. This idea lies at the centre of his ‘thermal time hypothesis’, which he developed alongside the French mathematician Alain Connes. Rovelli also discusses the humbling perspective that arises from the distinction between how we perceive the world and the deeper reality that underlies it.