Premise: Frederick "Dennis" Greene (January 11, 1949 – September 5, 2015) was an American singer who was a member of Sha Na Na who were formed in 1969 at Columbia University in New York as the Columbia Kingsmen. The name change to Sha Na Na occurred because of another group with a similar name, which was known for the song Louie Louie.
Hypothesis: Frederick "Dennis" Greene lived in the 20th century and 21st century.