Adam G. Riess

Biography

Adam Guy Riess, born on December 16, 1969, in Washington, D.C., has become one of the most influential astrophysicists of the early 21st century. He attended Watchung Hills Regional High School for his early education, then went on to study at Harvard University, Massachusetts Institute of Technology, and the University of California, Berkeley. This academic background prepared him for groundbreaking research in cosmology that changed our understanding of the universe.

Riess became a leading expert in using Type Ia supernovae to measure distances across the universe with remarkable precision. He carefully observed these stellar explosions in distant galaxies and used advanced analysis methods to understand how the universe's expansion rate has changed over time. This approach was key to one of the most important cosmological discoveries of recent times.

In the late 1990s, as part of the High-Z Supernova Search Team, Riess helped discover that the universe's expansion is speeding up instead of slowing down, as many had expected. This finding challenged the belief that gravity would slow cosmic expansion over time. The acceleration suggested the presence of a mysterious force or energy, now known as dark energy, which makes up about 70 percent of the universe's total energy.

Riess is a Bloomberg Distinguished Professor at Johns Hopkins University and a researcher at the Space Telescope Science Institute. He continues to perfect measurements of cosmic expansion. His recent work has brought attention to the "Hubble tension," a major difference between local measurements of the universe's current expansion rate and values from the early universe. This tension points to possible errors in the measurement methods or the need for new physics beyond the standard cosmological model.

Riess has been honored by the scientific community with many prestigious awards, including the 2011 Nobel Prize in Physics, shared with Saul Perlmutter and Brian Schmidt. He has also received the MacArthur Fellowship in 2008, the Shaw Prize in Astronomy in 2006, and the Breakthrough Prize in Fundamental Physics in 2015, marking him as one of the most celebrated scientists of his time.