In 1900, David Hilbert stood up in Paris and listed 23 problems he believed would define the next century of mathematics. The twelfth is still open. This week, a professor at IISc Bengaluru won the Ramanujan Prize for work that moved it forward. His name is Mahesh Kakde. He was born in 1983, took his Bachelor of Mathematics at the Indian Statistical Institute in Bangalore, then went to Cambridge for his master's and his PhD in pure mathematics, which he finished in 2008. After that he was an instructor at Princeton, a research associate at University College London, and then at King's College London. In 2019 he came back to Bangalore, as a professor at IISc. His field is algebraic number theory, which uses the machinery of abstract algebra to answer questions about ordinary whole numbers. Hilbert's twelfth problem asks for something that sounds modest and is not. Given a number system, write down an explicit recipe for building a particular family of larger ones. For the simplest cases mathematicians had known how to do this for a long time. In general, nobody did. Working with Samit Dasgupta, Kakde produced results on the Gross-Stark and Brumer-Stark conjectures that supplied exactly that kind of explicit construction where none had existed. The ICTP citation also singles out his fundamental results in noncommutative Iwasawa theory. He received the Infosys Prize in Mathematical Sciences in 2022, and was an invited speaker at the International Congress of Mathematicians alongside Dasgupta. The Ramanujan Prize is awarded jointly by the ICTP and the International Mathematical Union to young mathematicians from developing countries who do outstanding work in difficult conditions. It carries $10,000. Ramanujan sailed to Cambridge in 1914 because there was nowhere in India that could hold a mind like his. He returned in 1919 and died the following year, aged 32. A century later, Kakde made the same journey to Cambridge. Then he came back to Bangalore, and the prize named after Ramanujan came to him here.