In New Perspectives on Einstein’s E = mc2 (World Scientific Publishing), Young Suh Kim *61 and Marilyn Noz examine the Bohr-Einstein problem and attempt to fill in the gaps. While Niels Bohr and Albert Einstein occasionally met to discuss physics, there are no records of any discussion about their relating interests: the hydrogen atom and the moving observer. Addressing this, Kim and Noz construct a model of the bound state in the Lorentz-covariant world. Kim is a professor emeritus in the Department of Physics at the University of Maryland.