They bring to 23 the number of UCSB faculty to become fellows of the academy.
Polchinski, a UCSB faculty member and research physicist since 1990, has spent much of his career working with string theory, which proposes that matter at its most basic level consists of tiny vibrating strings.
The theory seeks to provide a unified depiction of all the forces and types of matter found in nature.
Murdoch, who joined the UCSB faculty in 1965, has worked extensively in population dynamics, particularly in the interactions between predators and prey and parasites and their hosts. He established the National Center for Ecological Analysis and Synthesis at UCSB. In addition, he is the Charles Storke II Professor of Ecology, Evolution and Marine Biology at UCSB, and is the director of UCSB's seven natural reserves.
The American Academy of Arts and Sciences was formed in 1780 by American founding fathers John Adams, John Hancock and others. Its current membership includes more than 150 Nobel laureates and more than 50 Pulitzer Prize winners.
Polchinski, Murdoch and other newly elected fellows will be formally inducted into the Academy Oct. 5, 2002, in a ceremony at its headquarters in Cambridge, Mass.