In an interview last weekend, Iran’s ambassador to the UN said that the nuclear enrichment of his country “would never stop” because it is authorized for “peaceful energy” purposes. This is the last development of a climbing of tensions on the Iranian nuclear program, which broke out when Israel targeted the country’s nuclear installations in June. To understand why the enrichment is so important, Madeleine Finlay speaks to Robin Grimes, professor of physics of materials at the Imperial College of London. He explains what is happening in the creation of a nuclear weapon, and why go to the stage of the weapon is so difficult
