In 1940−1946, he was professor of physics at the National Technical University of Athens, where he gave seminars on the theory of relativity, and worked in relative isolation during the German occupation of that country.
1940 bis 1946 war er Physik-Professor am Polytechnikum in Athen, wo er Seminare über die Relativitätstheorie hielt und er arbeitete während der deutschen Besatzung in relativer Isolation.