In George Lucas's classic 1980 film'The Empire Strikes Back', hero Han Solo (Harrison Ford) is frozen in carbonite by the evil Darth Vader. The fictional metal hardened around the heroic space smuggler as it cooled – sealing him in a state of'perfect hibernation'. Carbonite is of course a fictional material, consigned to the realms of the Star Wars galaxy far, far away. But according to one scientist, this scene is not completely the stuff of science-fiction. Dr Alex Baker, a chemist at the University of Warwick, thinks humans could potentially be frozen like Solo with a real-life equivalent.

China has banned the export of rare but critical earth minerals used in the manufacture of important semiconductors to the United States in the latest move in an ongoing tech war between the two superpowers. Beijing's announcement on Tuesday came just one day after the US ramped up restrictions on the export of advanced chips to China, which affects the country's ability to develop advanced weapons systems and artificial intelligence. So why is a "tech war" brewing between China and the US, and why does it matter? For months, the two countries have been involved in tit-for-tat export restrictions. The US hopes to cripple China's military and artificial intelligence (AI) advances as well as hamper its ambitions to become a global leader in clean energy and other technologies.