During the early years of the twentieth century, Albert Einstein 's theory of relativity caused bitter controversy within the worldwide physics community. There were many physicists, especially the "old guard", who were suspicious of the intuitive meanings of Einstein's theories. While the response to Einstein was based partly on his concepts being a radical break from earlier theories, there was also an anti-Jewish element to some of the criticism. The leading theoretician of the Deutsche Physik type of movement was Rudolf Tomaschek, who had re-edited the famous physics textbook Grimsehl's Lehrbuch der Physik. In that book, which consists of several volumes, the Lorentz transformation was accepted, as well as the old quantum theory. However, Einstein's interpretation of the Lorentz transformation was not mentioned, and Einstein's name was completely ignored. Many classical physicists resented Einstein's dismissal of the notion of a luminiferous aether, which had been a mainstay of their work for the majority of their productive lives. They were not convinced by the empirical evidence for relativity. They believed that the measurements of the perihelion of Mercury and the null result of the Michelson–Morley experiment might be explained in other ways, and the results of the Eddington eclipse experiment were experimentally problematic enough to be dismissed as meaningless by the more devoted doubters. Many of them were very distinguished experimental physicists, and Lenard was himself a Nobel laureate in Physics.