British physicist and science communicator Professor Jim Al-Khalili has questioned the efforts of wealthy individuals seeking to dramatically extend human life or achieve immortality. He argues that people should focus on making the most of their limited time rather than trying to live forever.
Al-Khalili is set to deliver the 2026 Royal Institution Christmas Lectures, where he will explore the science of time, including its nature, direction and the possibility of time travel. The Royal Institution says the lectures will examine how Einstein’s theory of relativity transformed humanity’s understanding of time.
According to modern physics, time does not pass at exactly the same rate under all circumstances. Differences in speed and gravitational fields can affect the rate at which clocks run, challenging the idea of a single universal clock.
Al-Khalili will also discuss the possibility of travelling through time. He says travelling into the past can be considered mathematically under certain conditions, but it creates difficult paradoxes. Travelling into the future, meanwhile, is theoretically more straightforward through effects associated with extremely high speeds or intense gravity.
Another major topic will be the “arrow of time”—the apparent fact that time moves in only one direction. Al-Khalili says he has developed an explanation for this long-standing scientific puzzle and plans to reveal it during the Christmas Lectures.
The Royal Institution says the 2026 lectures will also explore whether past, present and future can be viewed as co-existing, whether time existed before the Big Bang and whether travelling into the future could be possible.
