Banach and Nikodym Bench in Kraków

One evening in 1916 Hugo Steinhaus was strolling through Kraków's Planty park when he suddenly overheard the words "Lebesgue integral". Intrigued, he approached two young men discussing mathematics – and so discovered Stefan Banach, the future co-founder of functional analysis. A bench with figures of Banach and Otto Nikodym stands in the Planty on Podzamcze Street, near the spot where this conversation probably took place.

History: a conversation that changed mathematics

In 1916 the Lebesgue integral was a recent discovery known only to specialists – today it is one of the basic concepts of higher mathematics. It was being discussed by Stefan Banach, a self-taught mathematician, and Otto Nikodym, a mathematics graduate from Lviv who taught at the Fourth Grammar School in Kraków. They usually walked around the city as a trio, together with Witold Wilkosz, Banach's school friend. Steinhaus joined in and told them about a problem he had long been working on. A few days later Banach brought him the solution.

In 1920 Banach moved to Lviv (then Lwów, in Poland) and became the leading figure of the Lwów School of Mathematics. He died there on 31 August 1945. Nikodym worked in Warsaw and Kraków and after the war emigrated to the USA, where he taught at Kenyon College in Ohio from 1948 to 1965. Both were among the founders of the Polish Mathematical Society in 1919.

The bench

The sculptures are by Kraków sculptor Professor Stefan Dousa, and the bench was unveiled on 14 October 2016, a hundred years after the conversation. It was created on the initiative of a committee set up by the dean of the Faculty of Mathematics and Computer Science at the Jagiellonian University and funded by the Kraków tech company Astor. The two mathematicians sit facing each other, mid-discussion, with space left between them so you can join in.

Tripto tip

The bench is on Podzamcze Street at the foot of Wawel Hill, on the walk through the Planty from Wawel towards the Main Market Square. Ten minutes is enough here. At the unveiling, Dr Krzysztof Ciesielski of the Jagiellonian University wondered whether a visit before the school-leaving maths exam might bring luck – a good excuse for a photo with two great scholars.