2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/79416The weak solution of Tanaka's SDE is not a function of the driving Brownian motion, and therefore it has no Wiener chaos expansion. However in some sense explained here it has a generalised chaos expansion involving infinite products of stochastic differentials accumulating at the minimum of the Brownian path. This is related to the existence of a non-classical noise richer than the usual white noise.6 pages, LaTex2eProbability60G20 (Primary) 60J65, 60H20 (Secondary)text