Her work focused on recursively enumerable sets and computational complexity theory, which was influential with both Soviet and US mathematicians in the 1970s.

Louise Schmir was born in Metz, Lorraine, France, on 14 June 1935 to Marjem (née Szafran) and Samuel Szmir.

She attended William Howard Taft High School in the Bronx and won a Westinghouse Science Talent Search award during her senior year.

[1] She was awarded a PhD in 1965; her doctorate thesis was on co-simple isols and was an advance in the Dekker-Myhil-Nerode theory on recursive equivalence types.

In 1970, she married fellow mathematician Richard Larson,[1] was diagnosed with breast cancer in 1974[4] and in 1975 was promoted to full professor.

In 1988, Hay had a relapse in her breast cancer but continued to work until her death on 28 October 1989 in Oak Park, Illinois.