What is the quantum apocalypse?

Experts have been warning of something called the "quantum apocalypse" – the point when quantum computers become a reality and render most methods of internet encryption useless. Boris Johnson promised in November that the UK would "go big" on quantum computing – a new and more powerful way of processing information, based on quantum physics. If you imagine a standard computer to be like a horse and cart, then a quantum computer is "more like a sports car – a huge leap forward", explained the BBC. The UK is aiming to secure 50% of the global quantum computing market by 2040, said The Guardian, by investing in the National Quantum Computing Centre in Harwell, Oxfordshire. But the US and China have already taken huge steps to revolutionise research in the field, with the Americans achieving a "dramatic lead in quantum computing patents", said Scientific American. A leaked Google research paper published in 2019 suggested that a computer designed by the tech giant had achieved "quantum supremacy" – defined by The Independent as the ability to perform "a calculation that was far beyond the reach of today's most powerful supercomputers".