Joseph Silk is Homewood Professor of Physics and Astronomy at Johns Hopkins University. He studied at Cambridge and earned his PhD from Harvard in 1968. Silk was a postdoctoral fellow at Cambridge and Princeton, and taught at the University of California, Berkeley, and the University of Oxford.  He joined Johns Hopkins in 2010.  Silk has written or co-authored more than 500 publications. He has conducted important early work on homogeneities in the cosmic microwave background and how they are influenced by density fluctuations in the matter of the early universe, in particular by a damping effect that bears his name. Silk was awarded the 2011 Balzan Prize for his pioneering work on the infant universe.