Brosl Hasslacher (May 13, 1941 – November 11, 2005) was a theoretical physicist. Brosl Hasslacher was born in New York City in 1941 and obtained a bachelor's in physics from Harvard University in 1962. He did his Ph.D. with D.Z. Freeman and C.N. Yang at the State University of New York at Stony Brook. After having several postdoctoral and research positions at Institute for Advanced Study in Princeton, New Jersey, Caltech, ENS in Paris, and CERN, he settled for more than twenty years at the Theoretical Division of the Los Alamos National Laboratory. There he was involved in theoretical, experimental, and numerical work in theoretical physics, high-energy physics, nonlinear dynamics, fluid dynamics, nanotechnology, and robotics. In the 1970s, he worked on the extended hadron model, collaborating with A. Neveu. During the 1980s, Hasslacher pioneered with Uriel Frisch and Yves Pomeau the lattice-gas method for discrete simulation of fluid flow. As part of the Los Alamos National Laboratory's Center for Nonlinear Studies, Hasslacher worked with Mitchell Feigenbaum and contributed ideas to chaos theory. In the 1990s, Hasslacher worked with Mark Tilden on several papers concerning Biomorphic engineering. He is largely credited for using nonlinear dynamics to describe and design Tilden's BEAM robotics. In 1994, Hasslacher's UNIX account (bhass) at Los Alamos National Laboratory was used by hacker Kevin Mitnick to break into computer security expert Tsutomu Shimomura's computers. He retired from Los Alamos National Laboratory in 2003. Notable papers B. Hasslacher, A. Neveu, "Dynamic charges in field theories", Nuclear Physics (1979). B. Hasslacher, M.J. Perry, "Spin networks are simplicial quantum gravity", Physics Letters (1981). Frisch, U., B. Hasslacher, and Y. Pomeau, "Lattice gas Automata for the Navier Stokes Equation"' Phys. Rev. Lett. (1986). B. Hasslacher, "Spontaneous curvature in a class of lattice field theories" Physica D(1991). B. Hasslacher, M.W. Tilden, "Living machines", Robotics and Autonomous Systems (1995). B. Hasslacher, DA Meyer, "Modeling dynamical geometry with lattice gas automata", (1998). Dashen, RF; Hasslacher, B; Neveu, "A Particle spectrum in model field theories from semiclassical functional integral techniques" Physical Review D (Particles and Fields); (1975) Frisch, U.; d'Humieres, D.; Hasslacher, B.; Lallemand, P.; Pomeau, Y.; Rivet, JP "Lattice gas hydrodynamics in two and three dimensions. " Complex Systems; (1987) Dashen, RF; Hasslacher, B; Neveu, A "Semiclassical bound states in an asymptotically free theory" Physical Review D (Particles and Fields); 1975; Christ, N.; Hasslacher, B.; Mueller, AH Light-cone behavior of perturbation theory. Physical Review