This is an announcement for the paper "Embeddings between weighted Copson
and Ces\`{a}ro function spaces" by Amiran Gogatishvili, Rza Mustafayev,
and Tugce Unver.
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.
Archive classification: math.FA
Mathematics Subject Classification: Primary 46E30, Secondary 26D10
Remarks: 25 pages
Submitted from: rzamustafayev(a)gmail.com
The paper may be downloaded from the archive by web browser from URL
http://front.math.ucdavis.edu/1507.07866
or
http://arXiv.org/abs/1507.07866