The behavior on the space L^∞(R^n) for the multilinear singular integral operator defined by TAf(x)=∫RnΩ(x-y)/|x-y|^n+1(A(x)-A(y)△A(y)(x-y))f(y)dy is considered, where 12 is homogeneous of deg...The behavior on the space L^∞(R^n) for the multilinear singular integral operator defined by TAf(x)=∫RnΩ(x-y)/|x-y|^n+1(A(x)-A(y)△A(y)(x-y))f(y)dy is considered, where 12 is homogeneous of degree zero, integrable on the unit sphere and has vanishing is considered, where Ω is homogeneous of degree zero, integrable on the unit sphere and has vanishingmoment of order one, A has derivatives of order one in BMO(R^n). It is proved that if Ω satisfies some minimum size condition and an L1-Dini type regularity condition, then for f ∈ L^∞(R^n), TAf is either infinite almost everywhere or finite almost everywhere, and in the latter case, TAf ∈ BMO(R^n).展开更多
文摘The behavior on the space L^∞(R^n) for the multilinear singular integral operator defined by TAf(x)=∫RnΩ(x-y)/|x-y|^n+1(A(x)-A(y)△A(y)(x-y))f(y)dy is considered, where 12 is homogeneous of degree zero, integrable on the unit sphere and has vanishing is considered, where Ω is homogeneous of degree zero, integrable on the unit sphere and has vanishingmoment of order one, A has derivatives of order one in BMO(R^n). It is proved that if Ω satisfies some minimum size condition and an L1-Dini type regularity condition, then for f ∈ L^∞(R^n), TAf is either infinite almost everywhere or finite almost everywhere, and in the latter case, TAf ∈ BMO(R^n).