English

On boundedness of discrete multilinear singular integral operators

Classical Analysis and ODEs 2010-10-21 v1

Abstract

Let m(ξ,η)m(\xi,\eta) be a measurable locally bounded function defined in R2\mathbb R^2. Let 1p1,q1,p2,q2<1\leq p_1,q_1,p_2,q_2<\infty such that pi=1p_i=1 implies qi=q_i=\infty . Let also 0<p3,q3<0<p_3,q_3<\infty and 1/p=1/p1+1/p21/p31/p=1/p_1+1/p_2-1/p_3. We prove the following transference result: the operator Cm(f,g)(x)=\bbbr\bbbrf^(ξ)g^(η)m(ξ,η)e2πix(ξ+η)dξdη {\mathcal C}_m(f,g)(x)=\int_{\bbbr} \int_{\bbbr} \hat f(\xi) \hat g(\eta) m(\xi,\eta) e^{2\pi i x(\xi +\eta)}d\xi d\eta initially defined for integrable functions with compact Fourier support, extends to a bounded bilinear operator from Lp1,q1(\bbbr)×Lp2,q2(\bbbr)L^{p_1,q_1}(\bbbr)\times L^{p_2,q_2}(\bbbr) into Lp3,q3(\bbbr)L^{p_3,q_3}(\bbbr) if and only if the family of operators Dm~t,p(a,b)(n)=t1p\12\12\12\12P(ξ)Q(η)m(tξ,tη)e2πin(ξ+η)dξdη {\mathcal D}_{\widetilde{m}_{t,p}} (a,b)(n) =t^{\frac{1}{p}}\int_{-\12}^{\12}\int_{-\12}^{\12}P(\xi) Q(\eta) m(t\xi,t\eta) e^{2\pi in(\xi +\eta)}d\xi d\eta initially defined for finite sequences a=(ak1)k1\bbbza=(a_{k_{1}})_{k_{1}\in \bbbz}, b=(bk2)k2\bbbzb=(b_{k_{2}})_{k_{2}\in \bbbz}, where P(ξ)=k1\bbbzak1e2πik1ξP(\xi)=\sum_{k_{1}\in \bbbz}a_{k_{1}}e^{-2\pi i k_{1}\xi} and Q(η)=k2\bbbzbk2e2πik2ηQ(\eta)=\sum_{k_{2}\in \bbbz}b_{k_{2}}e^{-2\pi i k_{2}\eta}, extend to bounded bilinear operators from lp1,q1(\bbbz)×lp2,q2(\bbbz)l^{p_1,q_1}(\bbbz)\times l^{p_2,q_2}(\bbbz) into lp3,q3(\bbbz)l^{p_3,q_3}(\bbbz) with norm bounded by uniform constant for all t>0t>0

Keywords

Cite

@article{arxiv.1010.4158,
  title  = {On boundedness of discrete multilinear singular integral operators},
  author = {Paco Villarroya},
  journal= {arXiv preprint arXiv:1010.4158},
  year   = {2010}
}
R2 v1 2026-06-21T16:31:26.228Z