This physicist names a theory that predicts an effective rate equation for a two-particle annihilating random walk. That theory named for this physicist calculates the flux at a particle’s surface to give a stochastic balance equation for diffusion-limited cluster aggregation. One equation named for this physicist, which is a specific case of the Kolmogorov-forward equation, features a position-dependent force and constant (*) diffusion coefficient and is the simplest drift–diffusion equation. (-5[1])A 1912 (-5[1])paper by this physicist introduced the concept of rectifying fluctuations to generate work, which Feynman later popularized as a “ratchet-and-pawl” (10[2])system. (-5[1])The fluctuation–dissipation theorem for a memoryless system yields the equation “D equals mu times T,” (10[1])which is named for (10[1])Einstein and this (10[2])physicist. (10[4])For 10 points, (10[1])name this pioneering Polish statistical physicist. ■END■ (10[1]0[3])