KOLKATA: Physicist Ashoke Sen, an alumnus of Presidency College and IIT Kanpur kn-own for his pioneering work on string theory, was on Thursday awarded Oskar Klein Medal, one of the highest honours in theoretical physics.Sen is the first Indian to receive the award, whose past recipients include Steven Weinberg, Hans Bethe, Peter Higgs and Stephen Hawking.Named after Swedish theoretical physicist Oskar Klein, the medal has been awarded every year since 1988 by Stockholm University and Nobel Committee for Physics of Royal Swedish Academy of Sciences.Sen delivered a lecture titled ‘Gravity from Strings and Strings from Gravity’ at Stockholm University’s AlbaNova Centre after receiving the award on Thursday.The Kolkata boy, now ICTS-Infosys Madhava Chair Professor at International Centre for Theoretical Sciences in Bengaluru, is internationally recognised for his work on S-duality, precision counting of black-hole entropy and string field theory, all of which have helped shape string theory.The theory seeks to provide a unified description of all matter and the forces between its constituents.String theory proposes that the elementary constituents of matter are tiny, one-dimensional strings rather than point particles. Ashoke Sen’s research showed that different string theories are versions of a single underlying theory. He also advanced the study of unstable D-branes and formulated the Sen Conjecture on open string tachyon condensation.The office of the principal scientific adviser to the government of India congratulated Sen on receiving the 2026 Oskar Klein Medal. “He is the first Indian physicist to receive this prestigious honour. His research has played a significant role in advancing modern string theory and deepening our understanding of fundamental physics,” it said in an X post.ICTS director Rajesh Gopakumar said, “It has been no less than wonderful having Ashoke with us and setting the tone for excellence here at ICTS.”Presidency University registrar Debajyoti Konar said, “Presidency University rejoices as alumnus Prof Ashoke Sen becomes the first Indian physicist to win Oskar Klein Medal. He played a pivotal role as a mentor after Presidency College was upgraded to Presidency University. This university is always getting inspired by his continuous support and contributions.”Born in Kolkata on July 15, 1956, Sen studied at Sailendra Sircar Vidyalaya before pursuing a BSc in physics at Presidency College, where physicist Amal Kumar Raychaudhuri inspired him. He completed his MSc at IIT Kanpur in 1978 and PhD at SUNY Stony Brook in 1982.His honours include the Breakthrough Prize in Fundamental Physics (2012), Dirac Medal (2014), Shanti Swarup Bhatnagar Prize (1994), Infosys Prize (2009) and Padma Bhushan (2013). He is a fellow of the Indian Academy of Sciences, Indian National Science Academy and Royal Society, London.Sen held positions at Fermilab and Stanford Linear Accelerator Center before working at Tata Institute of Fundamental Research and Harish-Chandra Research Institute, where he was a distinguished professor. He has also been associated with National Institute of Science Education and Research and IISER Bhopal, and holds appointments at MIT and Korea Institute for Advanced Study as Morningstar Visiting Professor and distinguished professor, respectively.
