Lettre d'Albert Einstein à Louis de Broglie - 15 février 1954 (1)

Page 1 February 15, 1954 Professor L. de Broglie Institut de France Academy of Sciences Paris, France Dear Mr. de Broglie, Yesterday I read a German translation of your essay on the question of quantum theory and determinism. I am familiar with this text and took great pleasure in reading your ideas that were very clearly set out. It is funny how everything looks more vivid and lively when it appears in my old familiar language. I'm writing to you now for a rather strange reason. I want to tell you how I was driven to my methodology, which sounds quite bizarre on the face of it. I must have appeared like the well-known desert bird, the ostrich, constantly burying its head in the relativistic sand so as not to have to face the evil quantum. In truth, like you, I am convinced that one must search for the substructure—the necessity of this is skillfully hidden in present quantum theory by applying the statistical form. However, I have long been convinced that this substructure cannot be found by constructive means from the known empirical behavior of physical things, because the necessary mental leap would be too great for human abilities. I did not come to this conclusion just as a result of many years of work, but also because of my experiences in gravitational theory. Gravitational theories were only determined due to a purely…