Roman Jackiw

Roman Wladimir Jackiw (/roʊˈmæn dʒæˈkiːv/; Ukrainian: Роман Володимир Яцків, Roman Volodymyr Yatskiv; 8 November 1939 – 14 June 2023) was a Polish-born American theoretical physicist and Dirac Medallist.

Born in Lubliniec, Poland in 1939 to a Ukrainian family, the family later moved to Austria and Germany before settling in New York City when Jackiw was about 10.

Jackiw earned his undergraduate degree from Swarthmore College and his PhD from Cornell University in 1966 under Hans Bethe and Kenneth Wilson. He was a professor at the Massachusetts Institute of Technology Center for Theoretical Physics from 1969 until his retirement. He retained his affiliation in emeritus status in 2019.

Jackiw co-discovered the chiral anomaly, which is also known as the Adler–Bell–Jackiw anomaly. In 1969, he and John Stewart Bell published their explanation, which was later expanded and clarified by Stephen L. Adler, of the observed decay of a neutral pion into two photons. This decay is forbidden by a symmetry of classical electrodynamics, but Bell and Jackiw showed that this symmetry cannot be preserved at the quantum level. Their introduction of an "anomalous" term from quantum field theory required that the sum of the charges of the elementary fermions had to be zero. This work also gave important support to the colour theory of quarks.

Jackiw is also known for Jackiw–Teitelboim gravity, a theory of gravity with one dimension each of space and time that includes a dilaton field. Sometimes known as the R = T model or as JT gravity, it is used to model some aspects of near-extremal black holes.

Jackiw married fellow physicist So-Young Pi, daughter of Korean writer Pi Chun-deuk. One of Jackiw's sons is Stefan Jackiw, an American violinist. The other is Nicholas Jackiw, a software designer known for inventing The Geometer's Sketchpad. His daughter, Simone Ahlborn, is an educator at Moses Brown School in Providence, Rhode Island.

Jackiw died 14 June 2023, at the age of 83.

• Heineman Prize, 1995
• On 26 May 2000, Jackiw received an honorary doctorate from the Faculty of Science and Technology at Uppsala University, Sweden