Bryna Rebekah Kra (born 1966) is an American mathematician and Sarah Rebecca Roland Professor at Northwestern University who is on the board of trustees of the American Mathematical Society and was elected the president of American Mathematical Society in 2021. As a member of American Academy of Arts and Sciences and National Academy of Sciences, Kra has made significant contributions to the structure theory of characteristic factors for multiple ergodic averages. Her academic work centered on dynamical systems and ergodic theory, and uses dynamical methods to address problems in

number theory Number theory (or arithmetic or higher arithmetic in older usage) is a branch of pure mathematics devoted primarily to the study of the integers and integer-valued functions. German mathematician Carl Friedrich Gauss (1777–1855) said, "Mat ...

and combinatorics.

Education and career

Kra was born in 1966 in

Boston Boston (), officially the City of Boston, is the state capital and most populous city of the Commonwealth of Massachusetts, as well as the cultural and financial center of the New England region of the United States. It is the 24th- mo ...

. She graduated with a bachelor's degree from

Harvard University Harvard University is a private Ivy League research university in Cambridge, Massachusetts. Founded in 1636 as Harvard College and named for its first benefactor, the Puritan clergyman John Harvard, it is the oldest institution of high ...

in 1988, and obtained her Ph.D. from Stanford University in 1995 under the guidance of Yitzhak Katznelson. She held postdoctoral positions at the

Hebrew University The Hebrew University of Jerusalem (HUJI; he, הַאוּנִיבֶרְסִיטָה הַעִבְרִית בִּירוּשָׁלַיִם) is a public research university based in Jerusalem, Israel. Co-founded by Albert Einstein and Dr. Chaim Weiz ...

in Jerusalem, the

University of Michigan , mottoeng = "Arts, Knowledge, Truth" , former_names = Catholepistemiad, or University of Michigania (1817–1821) , budget = $10.3 billion (2021) , endowment = $17 billion (2021)As o ...

, the IHÉS and the

Ohio State University The Ohio State University, commonly called Ohio State or OSU, is a public land-grant research university in Columbus, Ohio. A member of the University System of Ohio, it has been ranked by major institutional rankings among the best publ ...

before joining the mathematics faculty at Pennsylvania State University as an assistant professor. Since 2004 Kra has been a professor of mathematics at

Northwestern University Northwestern University is a private research university in Evanston, Illinois. Founded in 1851, Northwestern is the oldest chartered university in Illinois and is ranked among the most prestigious academic institutions in the world. Charte ...

, where she was department chair from 2009 to 2012.

Book

With Bernard Host, Kra is the author of the book ''Nilpotent Structures in Ergodic Theory'' ( Mathematical Surveys and Monographs 236,

American Mathematical Society The American Mathematical Society (AMS) is an association of professional mathematicians dedicated to the interests of mathematical research and scholarship, and serves the national and international community through its publications, meetings, ...

, 2018).

Honors

In 2010 Kra was awarded the Levi L. Conant Prize for her expository article "The

Green–Tao theorem In number theory, the Green–Tao theorem, proved by Ben Green and Terence Tao in 2004, states that the sequence of prime numbers contains arbitrarily long arithmetic progressions. In other words, for every natural number ''k'', there exist arith ...

on arithmetic progressions in the primes: an ergodic point of view". In 2006 she was an

invited speaker at the International Congress of Mathematicians This is a list of International Congresses of Mathematicians Plenary and Invited Speakers. Being invited to talk at an International Congress of Mathematicians has been called "the equivalent, in this community, of an induction to a hall of fame." ...

Madrid Madrid ( , ) is the capital and most populous city of Spain. The city has almost 3.4 million inhabitants and a Madrid metropolitan area, metropolitan area population of approximately 6.7 million. It is the Largest cities of the Europ ...

("From combinatorics to ergodic theory and back again"), and was named an AMS Centennial Fellow the same year. In 2012 she became a fellow of the American Mathematical Society. In 2016 she became a fellow of the

American Academy of Arts and Sciences The American Academy of Arts and Sciences (abbreviation: AAA&S) is one of the oldest learned societies in the United States. It was founded in 1780 during the American Revolution by John Adams, John Hancock, James Bowdoin, Andrew Oliver, a ...

. In 2019, she was elected to the National Academy of Sciences. She was named a 2021 Simons Fellows in Mathematics. Kra was elected to the 2023 class of fellows of the

Association for Women in Mathematics The Association for Women in Mathematics (AWM) is a professional society whose mission is to encourage women and girls to study and to have active careers in the mathematical sciences, and to promote equal opportunity for and the equal treatment o ...

"for her vision and work creating programs to support women in mathematics, especially GROW (Graduate Research Opportunities for Women) and AWM student chapters; for her leadership in the mathematics community, including serving on the AWM Executive Committee and serving as president of AMS; and for making advocacy for women a priority throughout her career." Kra was elected president of the

and assumed that position on February 1, 2023.

Family relations

Kra is the daughter of mathematician Irwin Kra.Irwin Kra
Math for America board, retrieved 2016-06-24.

References

External links

Homepage at Northwestern UniversityPortrait at Northwestern University
{{DEFAULTSORT:Kra, Bryna 20th-century American mathematicians 21st-century American mathematicians American women mathematicians Living people 1966 births Stanford University alumni Harvard University alumni Pennsylvania State University faculty Northwestern University faculty Fellows of the American Mathematical Society Place of birth missing (living people) University of Michigan faculty Fellows of the American Academy of Arts and Sciences Members of the United States National Academy of Sciences 20th-century women mathematicians 21st-century women mathematicians 20th-century American women 21st-century American women