Sara Cosette Billey is an American mathematician working in algebraic combinatorics. She is known for her contributions on Schubert polynomials, singular loci of Schubert varieties, Kostant polynomials, and Kazhdan–Lusztig polynomials^[2] often using computer verified proofs. She is currently a professor of mathematics at the University of Washington.^[3]

Billey did her undergraduate studies at the Massachusetts Institute of Technology, graduating in 1990.^[3] She earned her Ph.D. in mathematics in 1994 from the University of California, San Diego, under the joint supervision of Adriano Garsia and Mark Haiman.^[4] She returned to MIT as a postdoctoral researcher with Richard P. Stanley, and continued there as an assistant and associate professor until 2003, when she moved to the University of Washington.^[3]

In 2012, she became a fellow of the American Mathematical Society.^[5]

• Sara, Billey; Lakshmibai, V. (2000). Singular loci of Schubert varieties. Boston: Birkhäuser. ISBN 9780817640927. OCLC 44750779.^[6]

• Billey, Sara; Haiman, Mark (1995). "Schubert polynomials for the classical groups". Journal of the American Mathematical Society. 8 (2): 443–482. doi:10.1090/s0894-0347-1995-1290232-1. ISSN 0894-0347.
• Billey, Sara; Warrington, Gregory (2003). "Maximal singular loci of Schubert varieties in 𝑆𝐿(𝑛)/𝐵". Transactions of the American Mathematical Society. 355 (10): 3915–3945. doi:10.1090/s0002-9947-03-03019-8. ISSN 0002-9947.
• Billey, Sara (1999). "Kostant polynomials and the cohomology ring for G/B". Duke Mathematical Journal. 96 (1): 205–224. doi:10.1215/S0012-7094-99-09606-0. ISSN 0012-7094. S2CID 16184223.

• "Sara Billey's Home Page".
• "AWM 2013 Essay Contest Winner writes about Sara Billey".
• Sara Billey publications indexed by Google Scholar