Quantum Mechanics was discovered by Heisenberg and Schrodinger forth years ago. It met with brilliant success when applied to elementary problems in atomic theory, such as the calculation of atomic and molecular spectra and simple scattering coefficients. But it ran into serious difficulties when it was extended to take into account the relativistic interaction of particles through the medium of fields. These difficulties have formed a barrier to the development of atomic theory.
During the last few years there has been a project, sponsored by the American Physical Society and American Philosophical Society, for collecting sources for the history of quantum mechanics. The leader of the project, Dr. Kuhn, has been traveling around interviewing the various early workers in the subject - those of them that are still alive - and collecting what information he can from them.
Two years ago e came to see me in Cambridge. I looked up my early work, some of it unpublished and long forgotten, to show it to him. In reading this early work again it appeared to me that some of the ideas I then had, though very immature, avoided to some extent the difficulties facing quantum theory at the present day. This can only mean that the course of development of quantum theory during all the intervening years has somewhere gone on the wrong track. It became necessary to go back and re-examine this development to try to see just what went wrong. I was thus led to some rather different ideas about the foundations of quantum mechanics.
Lecture given by Paul A. M. Dirac at the Lindau Nobel Laureate Conference concerning the basis of quantum mechanics and the recent problems quantum theory faced.
