Igor Klebanov is a theoretical physicist known for his work on quantum field theory and string theory. He is recognized in particular for his many years of research on the precise correspondence between these two subjects, which is called the gauge/string duality or the Anti-de Sitter/Conformal Field Theory correspondence. Klebanov was born in the Soviet Union and at the age of 16 moved to the United States with his family. A year later he enrolled at the Massachusetts Institute of Technology, graduating in 1982 with an S. B. in Physics. Klebanov defended his Ph.D. in theoretical high-energy physics at Princeton University in 1986. After three years of post-doctoral research at the Stanford Linear Accelerator Center, Klebanov returned to Princeton University as a faculty member. Currently, he is the Eugene Higgins Professor in the Department of Physics and Associate Director of the Princeton Center for Theoretical Science. Klebanov is a fellow of the American Academy of Arts and Sciences and a member of the National Academy of Sciences. His honors include the 2014 Tomassoni Prize from the Sapienza University of Rome.

Research Interests

Much of Klebanov's research has been focused on the exact relations between quantum field theories in four and three space-time dimensions, and higher dimensional theories which include gravity. He has made many contributions to the formulation of the "AdS/CFT dictionary," which relates scaling dimensions and correlation functions in conformal field theory to semi-classical dynamics in the Anti-de Sitter (AdS) space. Klebanov and collaborators have also constructed a tractable gravitational description of a gauge theory which is nearly scale invariant at short distances, but exhibits color confinement at long distances.

More recently, Klebanov and collaborators studied connections between the gravitational theories in AdS space containing interacting fields of spin greater than two, and O(N) symmetric conformal field theories in three space-time dimensions. Such conformal theories have applications to condensed matter and statistical physics, and Klebanov is studying them actively.

In 2011 Klebanov took part in proposing the F-theorem, which constrains renormalization group flows for three-dimensional quantum field theories. The positive quantity F that decreases along the flow from one three-dimensional CFT to another is the free energy on the three-dimensional sphere. F is also related to the quantum entanglement entropy, which has been the subject of much recent work by Klebanov and many others.

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Section 13: Physics