{ "id": "0908.4380", "version": "v2", "published": "2009-08-31T19:59:26.000Z", "updated": "2009-08-31T23:35:20.000Z", "title": "Littlewood-Paley characterization for $Q_α(R^n)$ spaces", "authors": [ "Qifan Li" ], "categories": [ "math.CA" ], "abstract": "In Baraka's paper [2], he obtained the Littlewood-Paley characterization of Campanato spaces $L^{2,\\lambda}$ and introduced $\\mathcal {L}^{p,\\lambda,s}$ spaces. He showed that $\\mathcal {L}^{2,\\lambda,s}=(-\\triangle)^{-\\frac{s}{2}}L^{2,\\lambda}$ for $0\\leq\\lambda