(FILES) Designated Director-General of the European Organization for Nuclear Research, (CERN) British physicist Mark Thomson poses for a portrait at the organization's offices in Meyrin, near Geneva, on November 7, 2024. The CERN physics laboratory chief welcomed China hitting pause on its major particle accelerator project, calling it an "opportunity" to ensure Europe's rival plan goes ahead. Ten years ago, China announced its intention to build the Circular Electron Positron Collider (CEPC), which would be the world's largest particle accelerator at 100 kilometres (62 miles) long. But Beijing recently put the project on ice, CERN's director-general Fabiola Gianotti told a small group of journalists in a recent briefing. (Photo by Fabrice COFFRINI / AFP via Getty Images)