Some have presumed that Fowler was the leader of the group because the writing and submission for publication were done at Caltech in 1956, but Geoffrey Burbidge has stated that this is a misconception. Fowler, though an accomplished nuclear physicist, was still learning Hoyle's theory in 1955 and later stated that Hoyle was the intellectual leader. The Burbidges also learnt Hoyle's theory during 1954–55 in Cambridge. "There was no leader in the group," G. Burbidge wrote in 2008, "we all made substantial contributions".