Jeremy Bernstein

‘Their aim​ is that we accept a capacity of ten thousand separative work units which is equivalent to ten thousand centrifuges of the older type that we already have,’ Ali Khamenei, Iran’s supreme leader, said on 4 June. ‘Our officials say we need 190,000 SWU. Perhaps this is not a need this year or in two years or five years, but this is the country’s absolute...

Nelson Mandela was released from prison on 2 February 1990. On 26 February F.W. de Klerk ordered the dismantling of a South African nuclear weapons programme which very few people knew existed. At the time the country had six uranium bombs and one more under construction. De Klerk had looked into abandoning the programme a year earlier, but Mandela’s release was plainly instrumental in...

I graduated from Harvard with a degree in mathematics in 1951 and got my PhD in physics in 1955. I needed a job and a friend made a suggestion: on the Harvard campus there was a relatively modest cyclotron, simple enough for graduate students to operate. There was a position open for a ‘house theorist’. My friend recommended me and I got the job. My only formal duties were to try...