Dirac Medallists 2019

The 2019 Dirac Medal and Prize is awarded to Viatcheslav Mukhanov (Ludwig-Maximilians- Universität, Munich), Alexei Starobinsky (Landau Institute for Theoretical Physics) and Rashid Sunyaev (Max-Planck Institute for Astrophysics, Garching) for their outstanding contributions to the physics of the Cosmic Microwave Background (CMB) with experimentally tested implications that have helped to transform cosmology into a precision scientific discipline by combining microscopic physics with the large scale structure of the universe.

Professor Mukhanov, in collaboration with G.Chibisov, discovered in 1981 the mechanism for the generation of scalar perturbations of the spacetime metric in a model of cosmological inflation proposed by Starobinsky. In 1985 he further developed a rigorous formalism to describe density perturbations in many inflationary models.

Professor Starobinsky in 1979 predicted gravity waves from a period of de Sitter-like evolution in the early universe and later proposed a version of cosmological inflation that is now described in terms of an extra curvature square term in the Einstein action. He wrote one of the first articles to compute density perturbations in slow-roll inflation and developed the formalism of stochastic inflation.

Professor Sunyaev, together with Ya. B. Zeldovich, predicted in 1970 the existence of acoustic peaks in the CMB. They also studied cosmological recombination, the surface of last scattering and the black- body photosphere of the universe. They discovered the decrease in brightness of the CMB in the direction of rich clusters of galaxies (Sunyaev-Zeldovich effect). This effect makes it possible to use clusters of galaxies as a powerful tool of observational cosmology.