 This way, many important questions about the planar models can be translated into exercises in Itō calculus.Indeed, several mathematically non-rigorous predictions made by physicists using conformal field theory have been proven using this strategy.If "D" is a simply connected, open complex domain not equal to C, and "γ" is a simple curve in "D" starting on the boundary (a continuous function with "γ"(0) on the boundary of "D" and "γ"((0, ∞)) a subset of "D"), then for each "t" ≥ 0, the complement "D""t" of "γ"([0, "t"]) is simply connected and therefore conformally isomorphic to "D" by the Riemann mapping theorem.