Ukraine's Maryna Viazovska yesterday became the second woman to be awarded the prestigious Fields medal, known as the Nobel prize for mathematics, alongside three others.

Viazovska, a 37-year-old Kyiv-born math professor, accepted the award at a ceremony in Helsinki as war raged in her home country.

The International Congress of Mathematicians, where the prize is awarded, was to have been in Russia's Saint Petersburg but was moved to the Finnish capital.

The other winners were France's Hugo Duminil-Copin (University of Geneva), Britain's James Maynard (Oxford University) and June Huh (Princeton) in the United States.

The medal is awarded every four years to between two and four people under 40 for mathematical achievement.

The only previous female awardee in the prize's more than 80-year history was Iranian Maryam Mirzakhani, who died of breast cancer in 2017 three years after winning.

Viazovska has been a professor at the Ecole Polytechnique Federale de Lausanne in Switzerland since 2017.

She was awarded for her work in sphere packing - a problem first posed by German astronomer and mathematician Johannes Kepler nearly 400 years ago.

He proposed the most compact way to pack spheres was in a pyramid. But that was not considered correct until 1998 with intense number-crunching. Then in 2016 Viazovska solved the problem in the eighth dimension with what is called an E8 lattice.

Duminil-Copin, born in France in 1985, is a professor at the Institut des Hautes Etudes Scientifiques, focusing on statistical physics.

Maynard, 35, specializes in analytic number theory, which led to major advances in understanding the structure of prime numbers.

Huh, 39, was awarded for "transforming the field of geometric combinatorics."

Huh said in a video played in Helsinki: "I grew up in Korea and I dreamed of becoming a poet to express the inexpressible. I eventually learned that mathematics is a way of doing that."

Maryna Viazovska

Top maths honor for Ukraine woman