When Alessandro Strumia, an Italian professor of theoretical physics, stood up at the Cern research centre in September last year to give a talk dismissing claims of sexism within his heavily male branch of science, he realised he was venturing into a sensitive area. Quite how sensitive became clear as soon as he began to speak.

It was wrong to claim the domination of physics by men was a product of discrimination, Strumia, 49, told his sceptical audience, many of them young women. He dismissed those who argued the contrary as “cultural Marxists” out to promote a “victimocracy of minorities”. Matters were not helped by the caption he had written for one of his slides: “Physics was invented and built by men”.

The reaction had