Nature: Nuclear reactors around the world produce highly enriched uranium for civilian research. Compared with the HEU in nuclear arsenals, the total amount of civilian HEU is modest (about 100 tons), yet not so modest that its proliferation implications can be discounted. Pablo Adelfang, the head of reactor research at the International Atomic Energy Agency, discussed the danger recently with Nature‘s Declan Butler.
An ultracold atomic gas can sync into a single quantum state. Researchers uncovered a speed limit for the process that has implications for quantum computing and the evolution of the early universe.