Results 81 to 90 of about 1,173,022 (231)
Beyond the Non‐Hermitian Skin Effect: Scaling‐Controlled Topology from Exceptional‐Bound Bands
ABSTRACT We establish a novel mechanism for topological transitions in non‐Hermitian systems that are controlled by the system size. Based on a new paradigm known as exceptional‐bound (EB) band engineering, its mechanism hinges on the unique critical scaling behavior near an exceptional point, totally unrelated to the well‐known non‐Hermitian skin ...
Mengjie Yang, Ching Hua Lee
wiley +1 more source
Toeplitz Operators on Symplectic Manifolds [PDF]
We study the Berezin-Toeplitz quantization on symplectic manifolds making use of the full off-diagonal asymptotic expansion of the Bergman kernel. We give also a characterization of Toeplitz operators in terms of their asymptotic expansion. The semi-classical limit properties of the Berezin-Toeplitz quantization for non-compact manifolds and orbifolds ...
Ma, Xiaonan, Marinescu, George
openaire +3 more sources
Hyponormality of Toeplitz operators with non-harmonic symbols on the Bergman spaces
In this paper, we present some necessary and sufficient conditions for the hyponormality of Toeplitz operator T φ $T_{\varphi }$ on the Bergman space A 2 ( D ) $A^{2}(\mathbb{D})$ with non-harmonic symbols under certain assumptions.
Sumin Kim, Jongrak Lee
doaj +1 more source
Let T1 be a generalized Calderón-Zygmund operator or ±I (the identity operator), let T2 and T4 be the linear operators, and let T3=±I. Denote the Toeplitz type operator by Tb=T1MbIαT2+T3IαMbT4, where Mbf=bf and Iα is the fractional integral operator.
Bijun Ren, Enbin Zhang
doaj +1 more source
Gysin sequences and SU(2)‐symmetries of C∗‐algebras
Motivated by the study of symmetries of C∗‐algebras, as well as by multivariate operator theory, we introduce the notion of an SU(2)‐equivariant subproduct system of Hilbert spaces. We analyse the resulting Toeplitz and Cuntz–Pimsner algebras and provide
Francesca Arici, Jens Kaad
doaj +1 more source
ABSTRACT Purpose Previous studies suggested that arterial‐input‐function (AIF) images are necessary to avoid signal saturation for pulmonary transit time (PTT) measurements. This study challenges that notion by investigating whether PTT can be accurately measured using blood pool signals from myocardial enhancement (non‐AIF) images during resting first‐
Mingyue Zhao +8 more
wiley +1 more source
Toeplitz Operators on the Weighted Bergman Space over the Two-Dimensional Unit Ball
We extend the known results on commutative Banach algebras generated by Toeplitz operators with radial quasi-homogeneous symbols on the two-dimensional unit ball.
Alma García, Nikolai Vasilevski
doaj +1 more source
Composition operator induced by ?(z) = sz + t for which |s|?1, |t|<1 and |s|+|t|?1
We study in this paper the composition operator that is induced by ?(z) = sz + t. We give a characterization of the adjoint of composiotion operators generated by self-maps of the unit ball of form ?(z) = sz + t for which |s|?1, |t|
Baghdad Science Journal
doaj +1 more source
Kernels of vector-valued Toeplitz operators [PDF]
Let $S$ be the shift operator on the Hardy space $H^2$ and let $S^*$ be its adjoint. A closed subspace $\FF$ of $H^2$ is said to be nearly $S^*$-invariant if every element $f\in\FF$ with $f(0)=0$ satisfies $S^*f\in\FF$.
Nicolas, Chevrot
core
Large Multi‐Response Linear Regression Estimation Based on Low‐Rank Pre‐Smoothing
ABSTRACT Pre‐smoothing is a technique aimed at increasing the signal‐to‐noise ratio in data to improve subsequent estimation and model selection in regression problems. However, pre‐smoothing has thus far been limited to the univariate response regression setting.
Xinle Tian +3 more
wiley +1 more source

