We completely characterize those positive Borel measures $mu$ on the unit ball $mathbb{B}_ n$ such that the Carleson embedding from Hardy spaces $H^p$ into the tent-type spaces $T^q_ s(mu)$ is bounded, for all possible values of $0<p,q,s<infty$.
We completely characterize the boundedness of the area operators from the Bergman spaces $A^p_alpha(mathbb{B}_ n)$ to the Lebesgue spaces $L^q(mathbb{S}_ n)$ for all $0<p,q<infty$. For the case $n=1$, some partial results were previously obtained by
Wu. Especially, in the case $q<p$ and $q<s$, we obtain the new characterizations for the area operators to be bounded. We solve the cases left open there and extend the results to $n$-complex dimension.
We establish that the Volterra-type integral operator $J_b$ on the Hardy spaces $H^p$ of the unit ball $mathbb{B}_n$ exhibits a rather strong rigid behavior. More precisely, we show that the compactness, strict singularity and $ell^p$-singularity of
$J_b$ are equivalent on $H^p$ for any $1 le p < infty$. Moreover, we show that the operator $J_b$ acting on $H^p$ cannot fix an isomorphic copy of $ell^2$ when $p e 2.$
We completely characterize the boundedness of the Volterra type integration operators $J_b$ acting from the weighted Bergman spaces $A^p_alpha$ to the Hardy spaces $H^q$ of the unit ball of $mathbb{C}^n$ for all $0<p,q<infty$. A partial solution to t
he case $n=1$ was previously obtained by Z. Wu in cite{Wu}. We solve the cases left open there and extend all the results to the setting of arbitrary complex dimension $n$. Our tools involve area methods from harmonic analysis, Carleson measures and Kahane-Khinchine type inequalities, factorization tricks for tent spaces of sequences, as well as techniques and integral estimates related to Hardy and Bergman spaces.
We study a Toeplitz type operator $Q_mu$ between the holomorphic Hardy spaces $H^p$ and $H^q$ of the unit ball. Here the generating symbol $mu$ is assumed to a positive Borel measure. This kind of operator is related to many classical mappings acting
on Hardy spaces, such as composition operators, the Volterra type integration operators and Carleson embeddings. We completely characterize the boundedness and compactness of $Q_mu:H^pto H^q$ for the full range $1<p,q<infty$; and also describe the membership in the Schatten classes of $H^2$. In the last section of the paper, we demonstrate the usefulness of $Q_mu$ through applications.
For $1<p<infty$ and $0<s<1$, let $mathcal{Q}^p_ s (mathbb{T})$ be the space of those functions $f$ which belong to $ L^p(mathbb{T})$ and satisfy [ sup_{Isubset mathbb{T}}frac{1}{|I|^s}int_Iint_Ifrac{|f(zeta)-f(eta)|^p}{|zeta-eta|^{2-s}}|dzeta||deta
|<infty, ] where $|I|$ is the length of an arc $I$ of the unit circle $mathbb{T}$ . In this paper, we give a complete description of multipliers between $mathcal{Q}^p_ s (mathbb{T})$ spaces. The spectra of multiplication operators on $mathcal{Q}^p_ s (mathbb{T})$ are also obtained.
We completely characterize the simultaneous membership in the Schatten ideals $S_ p$, $0<p<infty$ of the Hankel operators $H_ f$ and $H_{bar{f}}$ on the Bergman space, in terms of the behaviour of a local mean oscillation function, proving a conjecture of Kehe Zhu from 1991.
We introduce a family of weighted BMO and VMO spaces for the unit ball and use them to characterize bounded and compact Hankel operators between different Bergman spaces. In particular, we resolve two problems left open by S. Janson in 1988 and R. Wallsten in 1990.
A full description of the membership in the Schatten ideal $S_ p(A^2_{omega})$ for $0<p<infty$ of the Toeplitz operator acting on large weighted Bergman spaces is obtained.
A description of the Bloch functions that can be approximated in the Bloch norm by functions in the Hardy space $H^p$ of the unit ball of $Cn$ for $0<p<infty$ is given. When $0<pleq1$, the result is new even in the case of the unit disk.
