Emanuel Derman
Emanuel Derman (born 1945) is a South African-born American physicist-turned-quantitative analyst, academic, and author renowned for bridging theoretical physics with financial modeling. After earning a PhD in theoretical particle physics from Columbia University in 1973 and conducting postdoctoral research in the field, Derman shifted to Wall Street in the 1980s, joining Salomon Brothers before moving to Goldman Sachs in 1985, where he rose to managing director and co-developed the Black-Derman-Toy (BDT) model—a foundational short-rate framework for pricing interest rate derivatives that calibrates to the yield curve and volatility structure.[1][2][3]
As head of quantitative strategies at Goldman Sachs until 2002, Derman advanced local volatility models, including the Derman-Kani binomial tree approach for equity derivatives.[1] He later served as Professor of Professional Practice in Financial Engineering at Columbia University, directing its master's program from 2003 to 2023, while authoring influential works like My Life as a Quant: Reflections on Physics and Finance (2004), which chronicles his career transition, and Models.Behaving.Badly: Why Confusing Illusion with Reality Can Lead to Disaster, Wall Street, and the Subprime Debacle (2011), which applies first-principles scrutiny to expose the flawed metaphysics and overconfidence in financial models' predictive power.[3][4] Derman's writings emphasize the irreducible gap between robust scientific theories and pragmatic, error-prone financial metaphors, advocating epistemic humility in quantitative risk management.[4]