ABSTRACT
Little did I know when I set out for a year in Moscow in September 1968 that I would meet and work with Yakov Borisovich Zeldovich. It all came about more or less by accident. I had completed my doctorate in the previous year in the Radio Astronomy Group at the Cavendish Laboratory at Cambridge, where I had studied with Martin Ryle and Peter Scheuer on the astrophysical and cosmological problems of extragalactic radio sources. In 1965, I had attended the third Texas Symposium in New York and had my first encounters with Soviet astrophysicists. At that time, because of the Cold War, scientists from the USSR were very rare visitors to the West, but on that occasion, Ginzburg and Novikov had been allowed to attend the meeting. In the following year, Ginzburg came to Cambridge and I was impressed by his enthusiasm and deep understanding of high energy astrophysical processes. Moscow was already a major centre for theoretical astrophysics and cosmology and I asked Ginzburg if he would be willing to accept me as a postdoctoral fellow at the Lebedev Institute, if I were successful in obtaining a Royal Society-USSR Academy of Sciences Exchange Fellowship to Moscow. My reason for wanting to work with Ginzburg and his colleagues was to work on the implications of the number counts of active galaxies for the origin of cosmic rays and related problems. I also knew somewhat more vaguely of the cosmological work being carried out in Moscow by cosmologists such as Zeldovich, Novikov, and their colleagues. It was an exciting prospect to find out exactly what was going on astrophysically and cosmologically at first hand in Moscow. My application to the Royal Society was successful, and I spent eight months in the language laboratory at Cambridge learning enough Russian to be able to talk science on their terms rather than mine. This was not exactly the best time to visit the Soviet Union-the invasion of Czechoslovakia had taken place only a couple of months earlier.
