In 1928, he obtained his doctorate degree from California Institute of Technology under Eric Temple Bell with thesis The Gravitational Field of a Body with Rotational Symmetry in Einstein's Theory of Gravitation.
1928年にはカリフォルニア工科大学でEric Temple Bell指導の下、論文The Gravitational Field of a Body with Rotational Symmetry in Einstein's Theory of Gravitationで博士号を取得した。