Maryam Mirzakhani; award-winning mathematician

STANFORD, Calif. (AP) — Maryam Mirzakhani, a Stanford University professor who was the first and only woman to win the prestigious Fields Medal in mathematics, has died. She was 40.

Mirzakhani, who battled breast cancer, died on Saturday, the university announced. It did not indicate where she died.

In 2014 Mirzakhani was one of four winners of the Fields Medal, which is presented every four years and is considered the mathematics equivalent of the Nobel Prize. She was named for her work on complex geometry and dynamic systems.

"Mirzakhani specialized in theoretical mathematics that read like a foreign language by those outside of mathematics: moduli spaces, Teichmüller theory, hyperbolic geometry, Ergodic theory and symplectic geometry," according to the Stanford press announcement. "Mastering these approaches allowed Mirzakhani to pursue her fascination for describing the geometric and dynamic complexities of curved surfaces, spheres, doughnut shapes and even amoebas — in as great detail as possible."

The work had implications in fields ranging from cryptography to "the theoretical physics of how the universe came to exist," the university said.

Mirzakhani was born in Tehran, Iran, and studied there and at Harvard University. She joined Stanford as a mathematics professor in 2008.

Iran's President Hassan Rouhani issued a statement Saturday praising Mirzakhani. "The grievous passing of Maryam Mirzakhani, the eminent Iranian and world-renowned mathematician, is very much heartrending," Rouhani said in a message that was reported by the Tehran Times.

Iran's foreign minister, Mohammad Javad Zarif, said her death pained all Iranians, the Tehran Times reported.