MacArthur Fellows Program

Matias Zaldarriaga

Cosmologist | Class of 2006

Analyzing faint signatures of the Big Bang and developing valuable interpretive tools to piece together the early history of the cosmos.

Harvard University
Cambridge, Massachusetts
35 at time of award
Published September 1, 2006

About Matias's Work

Matias Zaldarriaga is a theoretical astrophysicist who analyzes faint signatures of the Big Bang to piece together the early history of the cosmos. Early in his career, Zaldarriaga co-wrote computer software known as CMBFAST that has become a standard tool for astronomers interpreting observations of the cosmic microwave background (CMB); it has been used to estimate the total density of mass and energy in the universe. His analyses reveal the power of CMB observations such as lensing and polarization to generate gravitational maps of the early universe and for exploring indirectly the properties of otherwise undetectable matter in the intervening space. Zaldarriaga is equally adept at identifying the interpretive pitfalls in analyzing experimental data; his insights have a direct impact on the design of telescopes that are currently being constructed. Recently, he and his colleagues have argued that the period after the Big Bang but before the formation of the first stars could be indirectly observed by examining variations in CMB at the 21 cm wavelength. This proposal may offer an experimental window into events that previously were only matters of conjecture. Though many of his studies are deeply rooted in observational astronomy, Zaldarriaga shows both a capacity and a propensity for integrating his results within a theoretical framework constructed on deep physical principles. 


Matias Zaldarriaga was born in Buenos Aires, Argentina in 1971 and received a Licenciado en Ciencias Fisicas (1994) from the University of Buenos Aires and a Ph.D. (1998) from the Massachusetts Institute of Technology. He was a Keck Visiting Professor at the Institute for Advanced Study (2001-2002) and an assistant professor at New York University (2001-2002), prior to joining the Departments of Astronomy and Physics at Harvard University as an associate professor in 2003. He is currently a professor of astronomy and physics at Harvard. His research has appeared in such journals as Physical Review D, the Astrophysical Journal, and Nature.

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Please credit: John D. and Catherine T. MacArthur Foundation

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