In two consecutive years, the California Institute of Technology (Caltech) has been ranked number one in the World University Ranking of Times Higher Education Supplement, and its Physical Sciences Program is also ranked number one. Its high energy theory group is focused on mathematical aspects of string theory and quantum field theory. John Schwarz is one of the founders of superstring theory. The other three professors in string theory, Anton Kapustin, Sergei Gukov and Hirosi Ooguri, are all joint appointments in the Mathematics Department, showing their strong ties to mathematics. Caltech has a world-renowned group in quantum information and quantum computation, including Alexei Kitaev, whose work has close connection to three-dimensional topology and topological field theory. In fact, Kitaev is also in a joint appointment with mathematics. The partnership between QGM and Caltech strengthens QGM's activities at further exciting interfaces between math and physics. Hirosi Ooguri is Fred Kavli Professor of Theoretical Physics and Mathematics and the Deputy Chair of the Division of Physics, Mathematics, and Astronomy (equivalent of Vice Dean of Physical Sciences) at Caltech. He is also one of the founders and a Principal Investigator of the Kavli Institute for the Physics and Mathematics of the Universe at the University of Tokyo. Ooguri is a world leader in topological quantum field theory and topological string theory. With Bershadsky, Cecotti, and Vafa, he laid the foundation of topological string theory and developed tools to compute its higher genus amplitudes. With Strominger and Vafa, he used topological strings to compute higher genus corrections to the black hole entropy. His work on two-dimensional conformal field theory, supersymmetric gauge theory and its connection to string theory, and applications of the holographic principle in quantum gravity are also highly regarded. He received the inaugural Eisenbud Prize for Mathematics and Physics from the American Mathematical Society in 2007, the Humboldt Research Award, and the Nishina Memorial Prize (the most prestigious physics prize in Japan) in 2008. In 2012, he was chosen as one of the inaugural Simons Investigators of the Simons Foundation and elected as an inaugural Fellow of the American Mathematical Society.

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