Quantum mechanics is an extraordinary branch of science. It’s a field where the boundary between fantasy and reality can start to blur. Imagine, for instance, a device that makes modern supercomputers look obsolete. It’s called a quantum computer. Quantum computers aren’t with us yet. But if and when they arrive, the impact could be colossal, reaching into every corner of our lives. From totally secure communication to new medical sensors that revolutionise healthcare and complex modelling that could engineer powerful new drugs to defeat pandemics – the possibilities are endless. This research is helping the U K stay at the forefront of the race to develop these remarkable machines. That means comprehending quantum mechanics’ most fundamental properties – and exploring the possibility of parallel universes that they imply.