John Wheeler, one of the world's most influential physicists, is best known for coining the term 'black holes', for his seminal contributions to the theories of quantum gravity and nuclear fission, as well as for his mind-stretching theories and writings on time, space and gravity.
What do you feel is the likely range of black holes in the universe, from smallest to largest?
Boy, that's a lovely question. The smallest black hole - I suspect [can] be made from the collapse of a neutron star that picks up some matter and by picking up this matter becomes more massive than the critical amount and collapses. I'm afraid I'm not being as imaginative as I could be in thinking of a way to get small black hole, but a mass of the a neutron star which is maybe two times the mass of the sun. And what's the biggest one. Well, how big would such a thing be? Well such a thing, a black hole would be about that big.
Ken Ford took his Ph.D. at Princeton in 1953 and worked with Wheeler on a number of research projects, including research for the Hydrogen bomb. He was Professor of Physics at the University of California and Director of the American Institute of Physicists. He collaborated with John Wheeler in the writing of Wheeler's autobiography, 'Geons, Black Holes and Quantum Foam: A Life in Physics' (1998).