*(Text by Jenneke Krüger)*

Karen Uhlenbeck (1942, Cleveland, Ohio, USA) is the eldest of four children; her mother, Carolyn Windeler Keskulla, was an artist and schoolteacher and her father, Arnold Keskulla, was an engineer. The family lived in a rural community; Karen liked (and likes) to spend time outdoors, but she also liked reading very much. In her own words: “*I used to read under the desk in school. … I was particularly interested in reading about science.*”

She enrolled at Michigan University to study physics; however, she discovered that she enjoyed mathematics much more than physics, so she decided to switch to mathematics. An added advantage in Karen’s mind was that in mathematics she could work on her own; at the time she didn’t like very much being involved with other people. That attitude changed gradually when she met more people with whom she could share her ideas on mathematics. She got her BSc in 1964, continued her studies at the Courant Institute in New York, married the biophysicist Olke Uhlenbeck and went with him to Boston, where she was awarded her MSc at Brandeis University in 1966. She remained at Brandeis for her PhD research, with Richard Palais as her adviser. Her doctoral thesis was titled *The Calculus of Variations and Global Analysis* (1968).

After finishing her PhD, Karen Uhlenbeck did not straight away see herself as a professional mathematician. She and her husband had temporary positions at MIT and the University of California in Berkeley, where she also took courses in general relativity and Lorentz-geometry (the geometry of space-time). In those years Karen Uhlenbeck realized that however good she was in mathematics, many universities did not want to hire women; in the early seventies the place of a woman was still seen as primarily at home. Her husband would be able to get a position at universities such as Princeton, MIT and Stanford, but these top ranking institutions would not hire her as well. When both she and her husband were offered a position at the University of Illinois, in Champaign-Urbana, they decided to accept and started working there in 1971.

However, Karen felt unhappy about the mathematics and the social environment. She travelled a lot thanks to a fellowship she received, and met and worked with other mathematicians such as Lesley Sibner and Jonathan Sachs. In 1976 Karen moved to Chicago, where she taught at the University of Illinois and from 1982 at the University of Chicago. She published many important papers on a variety of subjects, both on her own and with other mathematicians, such as J. Sachs, R. Schoen and S.-T. Yau.

Around that time she also became a strong advocate for greater gender diversity in mathematics and sciences. In 1987 she became a mathematics professor at the University of Texas, Austin. In 1990 she was the second woman who gave a plenary lecture at the International Congress of Mathematicians; the first woman was Emmy Noether, in 1932. She remained at the University of Texas until her retirement. She is still an active member of academia in the University of Texas at Austin and the Institute for Advanced Study in Princeton.

Karen Uhlenbeck made it to headlines worldwide in early 2019 when it was announced that she had been awarded the Abel prize –the equivalent of the Nobel prize in mathematics. Even though the Abel prize has been awarded yearly since 2003, Uhlenbeck was the first woman to receive this honour. Congratulations to her and let’s hope that many more will come!

Sources:

http://celebratio.org/Uhlenbeck_K/cover/472/

www.quantamagazine.org/karen-uhlenbeck-uniter-of-geometry-and-analysis-wins-abel-prize-20190319/

Jim Al-Khalili (2019). A biography of Karen Uhlenbeck. www.abelprize.no