Bruce Winstein (25 September 1943, Los Angeles – 28 February 2011) was an experimental physicist and cosmologist noted for his early work in elementary particle physics, particularly work toward demonstrating a serious asymmetry between particles and their anti-particles (CP violation).
From 1962 to 1964 he played a major role in all phases of the memorable experiment at Brookhaven's accelerator where the CP violation phenomenon in weak interactions was discovered.