After the end of World War II, both Einstein and Oppenheimer lived and worked in Princeton at the Institute for Advanced Study, Einstein became a professor there while Oppenheimer its director and a professor of physics from 1947 to 1966. They had their offices down the hall from each other. Einstein and Oppenheimer became colleagues and conversed with each other occasionally. They saw each other socially, with Einstein once attending dinner at the Oppenheimers in 1948. At the Institute, Oppenheimer considered general relativity to be an area of physics that wouldn't be of much benefit to the efforts of physicists, partly due to lack of observational data and due to conceptual and technical difficulties. He actively prohibited people from taking up these problems at the institute. Furthermore he forbade Institute members from having contacts with Einstein. For one of Einstein's birthdays, Oppenheimer gifted him a new FM radio and had an antenna installed on his house so that he may listen to New York Philharmonic concerts from Manhattan, about 50 miles away from Princeton. Oppenheimer did not provide an article to the July 1949 issue of Reviews of Modern Physics, which was dedicated to the seventieth birthday of Einstein.