A “possible real solution to the energy crisis” that “could change everything”. That’s how recent headlines billed the mundane lumps of a dirty-looking material known as LK-99 reported by scientists in South Korea in July. Their findings were described in two papers (https://arxiv.org/abs/2307.12008 and https://arxiv.org/abs/2307.12037) posted to the arXiv preprint server – a website where researchers present work that has not yet been subjected to peer review. They said they had “for the first time in the world” made a superconductor that worked at room temperature and at everyday pressure. A superconductor is a material that can conduct an electric...