Callan (TV series) is run by Colonel Hunter. ("Hunter" is a pseudonym for the current Section Chief, like the C of SIS.) The Section removes those who pose a danger to the "innocent" by persuasion, blackmail, extortion or death. David Callan had been the Section's top operator but he had become too curious about his targets and the rationale for their removal. The Section considered him vulnerable, volatile and dangerous and had laid him off to a dead-end book-keeping job for an ungrateful employer. ABC then commissioned a series of six episodes in 1967. In the first episode Callan rejoins the section in
Curtis Callan students include Philip Argyres, Vijay Balasubramanian, William E. Caswell, Peter Woit, Igor Klebanov, Juan Maldacena, Larus Thorlacius, Alberto Güijosa and Justin B. Kinney. Callan is best known for his work on broken scale invariance (Callan–Symanzik equation) and has also made leading contributions to quantum field theory and string theory in the areas of dyon-fermion dynamics, string solitons and black holes. Callan has been a member of the JASON defense advisory group since 1968, and was chair of the group from 1990 to 1995. He served as president of the American Physical Society in 2010. Curtis Callan Curtis Gove Callan Jr.