In March 1920, Nobel joined the Preußische Staatsbibliothek as a librarian and in the same year, he successfully defended his habilitation thesis, a work on Indian poetics. He received his teaching qualification in Indian philology at the University of Berlin in 1921. At the same time, he learned Chinese, Tibetan and Japanese and devoted himself to the research in Buddhist Studies. In 1927, Nobel was appointed extraordinary professor in Berlin. On April 1, 1928, he accepted a professorship for indology at the University of Marburg, which he held until his retirement in 1955. He did not try to ingratiate himself with national socialism, although he had, in November 1933, been one of the signers of the confession of professors at German universities and colleges to Adolf Hitler and the nationalsocialist state. His successor on the Marburg chair was Wilhelm Rau; Claus Vogel is one of Nobel's Marburg pupils. Nobel's extensive studies and critical editions of Suvaraprabhāsasūtra, one of the most important Mahāyāna-Sūtras, appeared between 1937 and 1958. In 1925, Nobel published the translation of the Amaruśataka by Friedrich Rückert. Nobel's study book, his personal files and some unpublished manuscripts, including a corrected German version of his habilitation thesis, were discovered in his former institute in 2008.
Selected publications
Suvarabhāsottamasūtra. Das Goldglanz-Sūtra: ein Sanskrittext des Mahāyāna-Buddhismus. Nach den Handschriften und mit Hilfe der tibetischen und chinesischen Übertragungen hrsg. Leipzig: Harrassowitz, 1937
Suvarnaprabhāsottamasūtra. Das Goldglanz-Sūtra: ein Sanskrittext des Mahāyāna-Buddhismus. Die tibetische Übersetzung mit einem Wörterbuch. Band 1: Tibetische Übersetzung, Stuttgart: Kohlhammer Verlag, 1944. Band 2: Wörterbuch Tibetisch-Deutsch-Sanskrit, Stuttgart: Kohlhammer Verlag, 1950
Suvarnaprabhāsottamasūtra. Das Goldglanz-Sūtra: ein Sanskrittext des Mahāyāna-Buddhismus. I-Tsing's chinesische Version und ihre tibetische Übersetzung. Volume 1: I-Tsing's chinesische Version. Volume 2: Die tibetische Übersetzung. Leiden: Brill, 1958
The Foundations of Indian Poetry and Their Historical Development. Calcutta 1925
Udrāyana, König von Roruka, eine buddhistische Erzählung; Wiesbaden, O. Harrassowitz, 1955.