Maximal Theorems for the Directional Hilbert Transform on the Plane
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چکیده
For a Schwartz function f on the plane and a non-zero v ∈ R2 define the Hilbert transform of f in the direction v to be Hvf(x) = p.v. ∫ R f(x− vy) dy y Let ζ be a Schwartz function with frequency support in the annulus 1 ≤ |ξ| ≤ 2, and ζf = ζ ∗ f . We prove that the maximal operator sup|v|=1|Hvζf | maps L2 into weak L2, and Lp into Lp for p > 2. The L2 estimate is sharp. The method of proof is based upon techniques related to the pointwise convergence of Fourier series.
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تاریخ انتشار 2003