Four members of the MIT faculty representing the departments of Economics, Mathematics, and Physics were recently named recipients of the 2019 Sloan Research Fellowships from the Alfred P. Sloan Foundation. The recipients, all early-career scholars in their fields, will each receive a two-year, $70,000 fellowship to further their research.

This year’s MIT recipients are among 126 scientists who represent 57 institutions of higher education in the United States and Canada. This year’s cohort brings MIT’s total to nearly 300 fellows — more than any single institution in the history of the fellowships since their inception in 1955.

Sloan Fellows are nominated by their fellow researchers and selected from an independent panel of senior scholars on “the basis of a candidate’s research accomplishments, creativity, and potential to become a leader in his or her field.”

2019 Sloan Fellow Nikhil Agarwal, the Castle Krob Career Development Assistant Professor of Economics in the School of Humanities, Arts, and Social Sciences, studies the empirics of matching markets.

“In these marketplaces, agents cannot simply choose their most preferred option from a menu with posted prices, because goods may be rationed or agents on the other side of the market must agree to a match,” Agarwal says of markets that include medical residency programs, kidney donation, and public school choice. “My research interests lie in how the market structure, market rules, and government policies affect economic outcomes in these settings. To this end, my research involves both developing new empirical techniques and answering applied questions,” he says.

Nancy Rose, department head and Charles P. Kindleberger Professor of Applied Economics, nominated Agarwal. “Nikhil [Agarwal] has made fundamental contributions to the empirical analysis of matching markets, advancing both economic science and public policy objectives,” says Rose.

Andrew Lawrie, an assistant professor in the Department of Mathematics, is an analyst studying geometric partial differential equations. He investigates the behavior of waves as they interact with each other and with their surrounding medium.

Lawrie's research focuses on solitons — coherent solitary waves that describe nonlinear dynamics as varied as rogue waves in the ocean, black holes, and short-pulse lasers. Together with Jacek Jendrej, a researcher at Le Centre National de la Recherche Scientifique and Université Paris 13, Lawrie recently gave the first mathematically rigorous example of a completely inelastic two-soliton collision.

“Dr. Lawrie's mathematical versatility and knowledge recently has been put on great display,” says one of Lawrie’s nominators of his paper in the research journal *Inventiones Mathematicae.* “This is one of those papers that completely describe mathematically an important phenomenon.”

“He has amassed an astonishingly broad and deep body of work for somebody who is only on his second year of a tenure track,” says his nominator, who requested anonymity.

Lawrie’s colleague Yufei Zhao was also named a 2019 Sloan Fellow recipient. Zhao, the Class of 1956 Career Development Assistant Professor in the Department of Mathematics, is a researcher in discrete mathematics who has made significant contributions in combinatorics with applications to computer science.

In major research accomplishments, Zhao contributed to a better understanding of the celebrated Green-Tao theorem, which states that prime numbers contain arbitrarily long arithmetic progressions. Zhao’s proof, co-authored with Jacob Fox, Zhao’s advisor and a former professor in the mathematics department, and David Conlon at the University of Oxford, simplifies a central part of the proof, allowing a more direct route to the Green-Tao theorem. Their work improves the understanding of pseudorandom structures — non-random objects with random-like properties — and has other applications in mathematics and computer science.

“The resulting proof is clean and fits in 25 pages, well under half the length of the original proof,” says Larry Guth, Zhao’s nominator and a professor of mathematics at MIT. “His expository work on the Green-Tao theorem is a real service to the community.”

The final 2019 Sloan Research Fellow recipient is Daniel Harlow, an assistant professor in the Department of Physics. Harlow researches cosmologic events, viewed through the lens of quantum gravity and quantum field theory.

“My research is focused on understanding the most extreme events in our universe: black holes and the Big Bang. Each year brings more observational evidence for these events, but without a theory of quantum gravity, we are not able to explain them in a satisfying way,” says Harlow, whose work has helped clarify many aspects of symmetries in quantum field theory and quantum gravity.

Harlow, who is a researcher in the Laboratory for Nuclear Science, has been working with Hirosi Ooguri, Fred Kavli Professor and director of the Walter Burke Institute for Theoretical Physics at Caltech, to give improved explanations of several well-known phenomena in the standard model of particle physics.

“We are very proud of Dan’s work with Ooguri on foundational aspects of symmetries in quantum field theory,” says Peter Fisher, department head and professor of physics.

“Sloan Research Fellows are the best young scientists working today,” says Adam F. Falk, president of the Alfred P. Sloan Foundation. “Sloan Fellows stand out for their creativity, for their hard work, for the importance of the issues they tackle, and the energy and innovation with which they tackle them. To be a Sloan Fellow is to be in the vanguard of 21st century science."