William Penney, Baron Penney, Gibraltar-born English mathematician, physicist, and academic (born 1909)

William George Penney, Baron Penney, was an English mathematician and professor of mathematical physics at the Imperial College London and later the rector of Imperial College London. He had a leading role in the development of High Explosive Research, Britain's clandestine nuclear programme that started in 1942 during the Second World War which produced the first British atomic bomb in 1952.