中文
相关论文

相关论文: Joint numerical radius of spherical Aluthge transf…

200 篇论文

Let $\mathbf{T} \equiv (T_1,\cdots,T_n)$ be a commuting $n$-tuple of operators on a Hilbert space $\mathcal{H}$, and let $T_i \equiv V_i P \; (1 \le i \le n)$ be its canonical joint polar decomposition (i.e.,…

泛函分析 · 数学 2019-10-22 Chafiq Benhida , Raul E. Curto , Sang Hoon Lee , Jasang Yoon

For an arbitrary commuting $d$--tuple $\bT$ of Hilbert space operators, we fully determine the spectral picture of the generalized spherical Aluthge transform $\dbT$ and we prove that the spectral radius of $\bT$ can be calculated from the…

泛函分析 · 数学 2020-06-08 Chafiq Benhida , Raul E. Curto , Sang Hoon Lee , Jasang Yoon

This paper explores refinements of some operator norm inequalities through the generalized spherical Aluthge transform and the spherical Heinz transform. We introduce the spherical Schatten $p$-norm for operator tuples and establish several…

泛函分析 · 数学 2025-04-01 Fuad Kittaneh , Satyajit Sahoo , Hranislav Stanković

The concepts of weighted numerical radius has been defined in recent times. In this article, we obtain several upper bound for weighted numerical radius of operators and $2 \times 2$ operator matrices which generalize and improves some well…

泛函分析 · 数学 2023-02-24 Raj Kumar Nayak

In this paper we give several expressions of spectral radius of a bounded operator on a Hilbert space, in terms of iterates of Aluthge transformation, numerical radius and the asymptotic behavior of the powers of this operator. Also we…

泛函分析 · 数学 2016-06-21 Fadil Chabbabi , Mostafa Mbekhta

The main aim of this article is to establish several $p$-numerical radius inequalities via the $(f,g)$-Aluthge transform of Hilbert space operators and operator matrices. Furthermore, various classical numerical radius and norm inequalities…

泛函分析 · 数学 2025-04-08 Satyajit Sahoo

Let $T$ be a bounded linear operator on a complex Hilbert space $\mathscr{H}.$ We obtain various lower and upper bounds for the numerical radius of $T$ by developing the Euclidean operator radius bounds of a pair of operators, which are…

泛函分析 · 数学 2023-08-21 Suvendu Jana , Pintu Bhunia , Kallol Paul

We develop a number of inequalities to obtain bounds for the numerical radius of a bounded linear operator defined on a complex Hilbert space using the properties of $t$-Aluthge transform. We show that the bounds obtained are sharper than…

泛函分析 · 数学 2024-08-13 Santanu bag , Pintu Bhunia , Kallol Paul

Let $A$ be a positive bounded linear operator acting on a complex Hilbert space $\big(\mathcal{H}, \langle \cdot\mid \cdot\rangle \big)$. Let $\omega_A(T)$ and ${\|T\|}_A$ denote the $A$-numerical radius and the $A$-operator seminorm of an…

泛函分析 · 数学 2020-04-20 Kais Feki

Let $T$ be a bounded linear operator on a Hilbert space. Then the Aluthge transform $\Delta T$ and the sequence $(\Delta^nT)$ of Aluthge iterates of $T$ are defined by \begin{align*} \Delta…

泛函分析 · 数学 2026-05-05 Neeru Bala

Let $A = U |A|$ be the polar decomposition of $A$. The Aluthge transform of the operator $A$, denoted by $\tilde{A}$, is defined as $\tilde{A} =|A|^{\frac{1}{2}} U |A|^{\frac{1}{2}}$. In this paper, first we generalize the definition of…

泛函分析 · 数学 2017-10-16 Mojtaba Bakherad , Khalid Shebrawi

Given a Hilbert module $H$ over a $C^*$-algebra, let $\mathcal{L}(H)$ be the set of all adjointable operators on $H$. For each $T\in\mathcal{L}(H)$, its numerical radius is defined by $w(T)=\sup\big\{\|\langle Tx, x \rangle\|: x\in H,…

泛函分析 · 数学 2025-02-28 J. Li , K. Wu , Q. Xu

We introduce the $\lambda$-mean transform $M_{\lambda}(T)$ of a Hilbert space operator $T$ as an extension of some operator transforms based on the Duggal transform $T^D$ by $M_{\lambda}(T) := \lambda T + (1-\lambda)T^D$, and present some…

泛函分析 · 数学 2020-04-29 Ali Zamani

Using the polar decomposition of a bounded linear operator $A$ defined on a complex Hilbert space, we obtain several numerical radius inequalities of the operator $A$, which generalize and improve the earlier related ones. Among other…

泛函分析 · 数学 2023-03-07 Pintu Bhunia

Let $A$ be a non-zero positive bounded linear operator on a complex Hilbert space $(\mathcal{H},\langle\cdot,\cdot\rangle)$. Let $\omega_A(T)$ denote the $A$-numerical radius of an operator $T$ acting on the semi-Hilbert space…

泛函分析 · 数学 2024-08-14 Pintu Bhunia , Kais Feki , Kallol Paul

In this article, we present some new inequalities for the numerical radius of products of Hilbert space operators and the generalized Aluthge transform. In particular, we show some upper bounds for $\omega(ABC+DEF)$ using the celebrated…

泛函分析 · 数学 2022-06-03 Mohammad Sababheh , Cristian Conde , Hamid Reza Moradi

Let $A$ be a positive (semidefinite) bounded linear operator acting on a complex Hilbert space $\big(\mathcal{H}, \langle \cdot\mid \cdot\rangle \big)$. The semi-inner product ${\langle x\mid y\rangle}_A := \langle Ax\mid y\rangle$, $x,…

泛函分析 · 数学 2020-04-01 Kais Feki

In this paper, we introduce a new type of parallelism for bounded linear operators on a Hilbert space $\big(\mathscr{H}, \langle \cdot ,\cdot \rangle\big)$ based on numerical radius. More precisely, we consider operators $T$ and $S$ which…

泛函分析 · 数学 2018-10-25 Marzieh Mehrazin , Maryam Amyari , Ali Zamani

We introduce a new seminorm of $n$-tuple operators, which generalizes the $A$-Euclidean operator radius of $n$-tuple bounded linear operators on a complex Hilbert space. We introduce and study basic properties of this seminorm. As an…

泛函分析 · 数学 2025-07-01 Pintu Bhunia , Messaoud Guesba

Let ${\mathbb B}(\mathscr H)$ denote the set of all bounded linear operators on a complex Hilbert space ${\mathscr H}$. In this paper, we present some norm inequalities for sums of operators which are a generalization of some recent…

泛函分析 · 数学 2023-10-10 Davood Afraza , Ramatollah Lashkaripoura , Mojtaba Bakherad
‹ 上一页 1 2 3 10 下一页 ›