Who Is The Mathematician Stefan Banach That Google Doodle Is Celebrating?

Banach was born in Kraków, Poland in 1892 - then part of then part of the Austro-Hungarian Empire. He never knew his mother, and his father sent him to be raised by family in the city.

Hugo Steinhaus, a distinguished mathematician, met and befriended a young Banach after overhearing them discussing new mathematic concepts. Steinhaus and Banach went on to become good friends and collaborate on groundbreaking work.

Steinhaus, an early founder of game and probability theory, referred to Banach as his “greatest scientific discovery.”

Alongside help from Steinhaus’ connections, Banach founded modern functional analysis, an entirely new branch of mathematics. Many concepts are named after him including Banach spaces, Banach algebra and the Banach-Steinhaus theorem.

Banach's work on modern functional analysis allowed him to become a professor at Lvov Technical University - in present day Lviv, Ukraine - a hundred years ago in 1922.

Throughout the twentieth century, he made major contributions to the theory of topological vector spaces, measure theory, integration, the theory of sets, orthogonal series and functional analysis, which is still studied and used today. 

Working for Weigl, who saved and sheltered Jews, prevented Banach and his co-workers from being arrested and deported to a concentration camp.

The Red Army freed the city in 1944 and Banach returned to re-establish the university after the war.

However, The Soviet Union was removing Poles from the area, so Banach began planning his return to his home country.

He was soon after diagnosed with lung cancer and was allowed to stay in Lviv. He died in August 1945, aged 53.

The Google Doodle in his honour is seen in the UK, Sweden, Iceland, Germany, Poland, Greece, Bulgaria, Israel, Australia and New Zealand.