Born: 10 March 1869 in Shavli/ Siaulai, Kovno ( Siaulai, Lithuania)

Died: 8 May 1953 in Moscow, USSR

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Benjamin Fedorovich Kagan's father Fedor Kagan was a clerk. Kagan

entered Novorossysky University in Odessa in 1887. He was expelled in

1889 for participating in the Democratic Students Movement. He was

sent to Ekaterinoslav in south-central Ukraine. The Soviets renamed

Ekaterinoslav in 1926 calling it Dnepropetrovsk.

In 1892 Kagan received a degree from Kiev University, then in 1895 he

was awarded a Master's Degree by St Petersburg University.

He taught at Novorossysky from 1897 until 1922, becoming a professor

there in 1917. However this was not his only post during this period

for he taught higher education classes for women and also taught at

the local Jewish school. As if this was not enough, Kagan also edited

the Journal of Experimental Physics and Elementary Mathematics from

1902 until 1917 and he was the director of a large publisher of

scientific materials Mathesis.

In 1922 he went to Moscow when the Department of Differential Geometry

was founded at Moscow State University. Kagan was the first Head of

Department and he founded an important School of Differential

Geometry. He retained his interest in publishing, however, and he was

the director of the science department of a state publisher for ten

years. He also directed the department of mathematics and natural

sciences of the Great Soviet Encyclopaedia.

In 1927, Kagan organised a seminar on vector and tensor analysis. He

founded a publication associated with this seminar Transactions of the

seminar on Vector and Tensor Analysis with its applications to

Geometry, Mechanics and Physics in 1933. In 1934 Kagan and other

members of his School organised an International conference on

differential geometry which took place at Moscow University.

Kagan worked on the foundations of geometry and his first work was on

Lobachevsky's geometry. In 1902 he proposed axioms and definitions

very different from Hilbert. Kagan studied tensor differential

geometry after going to Moscow because of an interest in relativity.

Kagan wrote a history of non-euclidean geometry and also a detailed

biography of Lobachevsky. He edited Lobachevsky's complete works which

appeared in five volumes between 1946 and 1951.

Article by: J J O'Connor and E F Robertson