Albert Allen Bartlett (March 21, 1923 – September 7, 2013) was an American professor of physics at the University of Colorado at Boulder. As of July 2001 Professor Bartlett had lectured over 1,742 times since September, 1969 on Arithmetic, Population, and Energy. Bartlett regarded the word combination "sustainable growth" as an oxymoron, and argued that modest annual percentage population increases could lead to exponential growth. He therefore regarded human overpopulation as "The Greatest Challenge" facing humanity.
