Education
He graduated from Brooklyn College in 1953 (with the assistance of tutoring from Karrass, who went to New York University) and went to Princeton University for graduate study in mathematics.
He graduated from Brooklyn College in 1953 (with the assistance of tutoring from Karrass, who went to New York University) and went to Princeton University for graduate study in mathematics.
The Baumslag–Solitar groups are named after him and Gilbert Baumslag, after their joint 1962 paper on these groups. Solitar competed on the mathematics team of Brooklyn Technical High School with his future co-author Abe Karrass, one year ahead of him in school. However, his intended mentor there, Emil Artin, was no longer interested in group theory, so he left with a masters degree and earned his doctorate from New York University instead, in 1958, under the supervision of Wilhelm Magnus.
Karrass remained on the faculty with Solitar, where they founded a summer institute for high school mathematics teachers.
Solitar moved to Polytechnic University in 1967, and then (as department chair) to York University in 1968, bringing Karrass with him. Solitar married J. Francien Hageman, a Dutch woman, in 1976.
He died of a heart attack on April 28, 2008.