Bruno Reynell analyses the phenomenal life and work of the late Stephen Hawking
“Remember to look up at the stars and not down at your feet.”
There are few individuals in the world of science whose passing could inspire the deluge of tributes that have been paid to Stephen Hawking, following his death on the morning of Wednesday 14th March. Fellow scientists, politicians, rock stars and many others have celebrated the physicist’s profound achievements, demonstrating the incredible breadth of his influence and popularity.
A towering figure in theoretical physics, Hawking’s career often revolved around the study of the nature of black holes. He identified them as the means for examining the relationship between Einstein’s theory of general relativity and quantum mechanics and, through his studies, he made several of the most important discoveries in the history of his field.
His first major breakthrough came in 1970 working alongside Roger Penrose, who had previously proven the existence of space-time singularities in black holes. The pair applied the same mathematics to the entire universe, and demonstrated that general relativity would also predict a singularity in the distant past – the origin of the Big Bang.
However, it is the discovery of Hawking radiation that is often cited as his greatest accomplishment. In 1974, Hawking theorised that the separation of particle-antiparticle pairs occurring at the event horizon of a black hole would result in the emission of radiation in the form of quantum particles. Currently, there are no techniques capable of observing Hawking radiation, meaning it is impossible to test for its existence, but the prediction alone has been compelling enough to secure place for Hawking in scientific history.
This discovery put forward further puzzles, especially the black hole information paradox that was resultant from it. Hawking radiation predicted the eventual disappearance of black holes. However, if physical information entering a black hole was being lost, that would violate a central tenet of quantum mechanics, namely that matter cannot be destroyed. Conversely, if the information escaped, that would be at odds with the theory of general relativity.
Hawking eventually ended up on the wrong side of the argument, but this just demonstrated that even when he was wrong, he was provoking debate. Yet, Hawking radiation remains a hugely important clue to the reconciliation of quantum mechanics and gravity, and a possible theory of everything. As Lord Rees, the astronomer royal, observed of the physicist, “Few, if any, of Einstein’s successors have done more to deepen our insights into gravity, space and time.”
Hawking was, however, more than just a scientist. Over time, he became a figure who transcended social and cultural boundaries, and a large part of this was through his being a symbol of triumph over great adversity.
Aged just 21, he was diagnosed with an unspecified disease, later identified to be the fatal degenerative motor neurone disease amyotrophic lateral sclerosis (ALS). He drastically defied the prognosis for how much time he had left, and conversely, used it to propel his work to new heights. To have achieved what he achieved in the face of his illness confirms his status as an enormously inspirational individual.
This contrast between physical frailty and brilliant intellect would bring Hawking considerable media attention, and the image of the inclined position he took up in his motorised wheelchair, as well as the sound of his speech synthesiser, became instantly recognisable. He would successfully take advantage of this to promote public interest in science.
A large part of this success would prove to come from A Brief History of Time, first published in 1988. Viewed by many as defining the popular science genre, the book has sold more than 10 million copies and been translated into more than 35 languages. Hawking manages to explain hugely complex ideas in layman’s terms, and the book remains one of the most brilliant and triumphant examples of science communication in history.
Indeed, it can be hard to say whether it was his academic contributions to science, or his capacity to draw others to the subject, that was more impressive. In either case, we can be thankful for what he accomplished during his life, as well as the gargantuan legacy he leaves behind.
Featured Image Credit: Wikimedia Commons