2021/06/26 by Qin, Moyan, Wu, Huoxiong, Xue, Qingying
#42B20 #Classical Analysis and ODEs (math.CA) #FOS: Mathematics
paper · doi:10.48550/arxiv.2106.14051
Let Ω be a function of homogeneous of degree zero and vanish on the unit sphere \mathbb Sn. In this paper, we investigate the limiting weak-type behavior for singular integral operator TΩ associated with rough kernel Ω. We show that, if Ω∈ Llog L(\mathbb Sn), then limλ→0+λ|\x∈ℝn:|TΩ(f)(x)|>λ\| = n-1‖Ω‖_L1(\mathbb Sn)‖f‖L1(ℝn), 0≤ f∈ L1(ℝn). Moreover,(n-1‖Ω‖_L1(\mathbbSn-1) is a lower bound of weak-type norm of TΩ when Ω∈ Llog L(\mathbbSn-1). Corresponding results for rough bilinear singular integral operators defined in the form TΩ(f1,f2) = TΩ1(f1)⋅ TΩ2(f2) have also been established.