Theoretical physicist Ashoke Sen wins 2026 Oskar Klein Medal

Theoretical physicist Ashoke Sen has won the 2026 Oskar Klein Medal, becoming the first Indian laureate to receive the honour. Stockholm University and the Nobel Committee for Physics of the Royal Swedish Academy of Sciences award the medal for contributions to theoretical physics. Dr. Sen is the ICTS-Infosys Madhava Chair Professor at the International Centre for Theoretical Sciences in Bengaluru. He delivered the memorial lecture accompanying the medal in Stockholm on October 22 under the title 'Gravity from Strings and Strings from Gravity'.

Career And Major Research

In his career, Dr. Sen has focused on string theory, which tries to describe matter and nature's fundamental forces within a single framework called quantum gravity. In the 1980s, he helped establish how equations for hypothetical strings relate to physical fields. In the 1990s, he helped show that two different ways to describe physical forces were equivalent, a concept called S-duality. He also proposed three related ideas known as the Sen conjectures in 1999. U.S. physicist Edward Witten called one of his papers short but brilliant and said it convinced him the duality had to be right. Dr. Sen also developed mathematical methods to explain a black hole's microscopic states.

Education And Awards

Dr. Sen graduated from Presidency College in Kolkata, attended IIT-Kanpur, and earned his PhD from Stony Brook University in New York in 1982. He has worked at the Tata Institute of Fundamental Research in Mumbai and the Harish-Chandra Research Institute in Prayagraj before moving to ICTS in 2021. His past honours include the S.S. Bhatnagar Prize, the Infosys Prize, the Breakthrough Prize in Fundamental Physics, the Dirac Medal, the Padma Shri, and the Padma Bhushan.

Context

The Oskar Klein Medal honors the Swedish physicist Oskar Klein, who explored whether electromagnetism and gravity could share a common framework. India has an influential community of string theorists spread across institutions like TIFR Mumbai, ICTS Bengaluru, and HRI Prayagraj.