{ "id": "1507.07866", "version": "v1", "published": "2015-07-28T17:38:59.000Z", "updated": "2015-07-28T17:38:59.000Z", "title": "Embeddings between weighted Copson and Cesàro function spaces", "authors": [ "Amiran Gogatishvili", "Rza Mustafayev", "Tuǧçe Ünver" ], "comment": "25 pages", "categories": [ "math.FA" ], "abstract": "In this paper embeddings between weighted Copson function spaces ${\\operatorname{Cop}}_{p_1,q_1}(u_1,v_1)$ and weighted Ces\\`{a}ro function spaces ${\\operatorname{Ces}}_{p_2,q_2}(u_2,v_2)$ are characterized. In particular, two-sided estimates of the optimal constant $c$ in the inequality \\begin{equation*} \\bigg( \\int_0^{\\infty} \\bigg( \\int_0^t f(\\tau)^{p_2}v_2(\\tau)\\,d\\tau\\bigg)^{\\frac{q_2}{p_2}} u_2(t)\\,dt\\bigg)^{\\frac{1}{q_2}} \\le c \\bigg( \\int_0^{\\infty} \\bigg( \\int_t^{\\infty} f(\\tau)^{p_1} v_1(\\tau)\\,d\\tau\\bigg)^{\\frac{q_1}{p_1}} u_1(t)\\,dt\\bigg)^{\\frac{1}{q_1}}, \\end{equation*} where $p_1,\\,p_2,\\,q_1,\\,q_2 \\in (0,\\infty)$, $p_2 \\le q_2$ and $u_1,\\,u_2,\\,v_1,\\,v_2$ are weights on $(0,\\infty)$, are obtained. The most innovative part consists of the fact that possibly different parameters $p_1$ and $p_2$ and possibly different inner weights $v_1$ and $v_2$ are allowed. The proof is based on the combination duality techniques with estimates of optimal constants of the embeddings between weighted Ces\\`{a}ro and Copson spaces and weighted Lebesgue spaces, which reduce the problem to the solutions of the iterated Hardy-type inequalities.", "revisions": [ { "version": "v1", "updated": "2015-07-28T17:38:59.000Z" } ], "analyses": { "subjects": [ "46E30", "26D10" ], "keywords": [ "cesàro function spaces", "optimal constant", "weighted copson function spaces", "combination duality techniques", "iterated hardy-type inequalities" ], "note": { "typesetting": "TeX", "pages": 25, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2015arXiv150707866G" } } }