David Bernard Alper Epstein (born 1937[1]) is a mathematician known for his work in hyperbolic geometry, 3-manifolds, and group theory, amongst other fields.

He returned to the UK in 1962 to become a research fellow of the newly founded Churchill College, Cambridge.

He then won a scholarship to the University of Cambridge, where he did Parts II and III of the Mathematical Tripos, graduating in 1957.

He returned to Cambridge in 1962, where he was an assistant lecturer at the university and director of studies at the new Churchill College.

At this stage, his father Ben was also having severe problems with the South African regime as a result of his ethical stand as a doctor.