English
Related papers

Related papers: Squash Operator and Symmetry

200 papers

We give a Hahn-Banach Characterization for convex-cyclicity. We also obtain an example of a bounded linear operator $S$ on a Banach space with $\sigma_{p}(S^*)=\emptyset$ such that $S$ is convex-cyclic, but $S$ is not weakly hypercyclic and…

Functional Analysis · Mathematics 2014-10-20 T. Bermúdez , A. Bonilla , N. Feldman

In this paper we obtain necessary and sufficient conditions for a linear bounded operator in a Hilbert space $H$ to have a three-diagonal complex symmetric matrix with non-zero elements on the first sub-diagonal in an orthonormal basis in…

Functional Analysis · Mathematics 2011-02-17 Sergey M. Zagorodnyuk

In this paper, we prove that there exist at least $n$ geometrically distinct brake orbits on every $C^2$ compact convex symmetric hypersurface $\Sg$ in $\R^{2n}$ satisfying the reversible condition $N\Sg=\Sg$ with $N=\diag (-I_n,I_n)$. As a…

Dynamical Systems · Mathematics 2016-12-14 Chungen Liu , Duanzhi Zhang

This work is a continuation of our previos paper \cite{Zel1}, where for the the Schr\"odinger operator $H=-\Delta+ V(\e)\cdot$ $(V(\e)\ge 0)$, acting in the space $L_2(\R^d)\,(d\ge 3)$, some constructive sufficient conditions for…

Spectral Theory · Mathematics 2019-06-07 Leonid Zelenko

We give a simple, straightforward proof of the non-hypercyclicity of an arbitrary (bounded or not) normal operator $A$ in a complex Hilbert space as well as of the collection $\left\{e^{tA}\right\}_{t\ge 0}$ of its exponentials, which,…

Functional Analysis · Mathematics 2019-09-30 Marat V. Markin , Edward S. Sichel

High-dimensional entanglement, captured by the Schmidt number, underpins advantages in quantum information tasks, yet a unified resource-theoretic description across different Buscemi-type operational objects has been missing. Here we…

Quantum Physics · Physics 2025-12-30 Xian Shi

Surface operators in four-dimensional gauge theories are two-dimensional defects, serving as natural generalizations of Wilson lines and 't Hooft line operators. They act as ideal probes for exploring the non-perturbative structure of the…

High Energy Physics - Theory · Physics 2025-12-10 Chuanzhong Li , Xiaoman Luo , Bao Shou

The Clifford operators are an important and well-studied subset of quantum operations, in both the qubit and higher-dimensional qudit cases. While there are many ways to characterize this set, this paper aims to provide an ideal…

Quantum Physics · Physics 2014-07-16 J. M. Farinholt

This thesis introduces a formal general framework for scaling blockchain protocols by sharding. The framework is modular and it can be adjusted for different needs or sets of assumptions. We prove that sharded protocols obtained by…

Cryptography and Security · Computer Science 2019-09-04 Zuphit Fidelman

Stabilizer codes are a simple and successful class of quantum error-correcting codes. Yet this success comes in spite of some harsh limitations on the ability of these codes to fault-tolerantly compute. Here we introduce a new metric for…

Quantum Physics · Physics 2018-05-30 Tomas Jochym-O'Connor , Aleksander Kubica , Theodore J. Yoder

We perform a non-perturbative study of the scale-dependent renormalisation factors of a complete set of dimension-six four-fermion operators. The renormalisation-group (RG) running is determined in the continuum limit for a specific…

High Energy Physics - Lattice · Physics 2018-08-15 Petros Dimopoulos , Gregorio Herdoíza , Mauro Papinutto , Carlos Pena , David Preti , Anastassios Vladikas

The current paper is devoted to the scattering theory of a class of continuum Schr\"{o}dinger operators with deterministic sparse potentials. We first establish the limiting absorption principle for both modified free resolvents and…

Spectral Theory · Mathematics 2015-06-17 Zhongwei Shen

Quantum key distribution (QKD) protocols make it possible for two parties to generate a secret shared key. One of the most important QKD protocols, BB84, was suggested by Bennett and Brassard in 1984. Various proofs of unconditional…

Quantum Physics · Physics 2022-08-26 Michel Boyer , Rotem Liss , Tal Mor

We study left symmetric bounded linear operators in the sense of Birkhoff-James orthogonality defined between infinite dimensional Banach spaces. We prove that a bounded linear operator defined between two strictly convex Banach spaces is…

Functional Analysis · Mathematics 2024-08-13 Kallol Paul , Arpita Mal , Pawel Wójcik

A bounded operator on a real or complex separable infinite-dimensional Banach space $Z$ is universal in the sense of Glasner and Weiss if for every invertible ergodic measure-preserving transformation $T$ of a standard Lebesgue probability…

Dynamical Systems · Mathematics 2015-12-18 Sophie Grivaux

For a symmetric system, we want to study the problem of crossing an hypersurface in the neighborhood of a given point, when we suppose that all of the available vector fields are tangent to the hypersurface at the point. Classically one…

Optimization and Control · Mathematics 2020-03-16 Pierpaolo Soravia

Despite enormous progress both in theoretical and experimental quantum cryptography, the security of most current implementations of quantum key distribution is still not established rigorously. One of the main problems is that the security…

Quantum Physics · Physics 2012-10-18 Marco Tomamichel , Charles Ci Wen Lim , Nicolas Gisin , Renato Renner

Since the invention of Bennett-Brassard 1984 (BB84) protocol, many quantum key distribution (QKD) protocols have been proposed and some protocols are operated even in field environments. One of the striking features of QKD is that QKD…

Quantum Physics · Physics 2016-01-18 Hiroki Takesue , Toshihiko Sasaki , Kiyoshi Tamaki , Masato Koashi

We introduce the notion of local orthogonality preserving operators to study the right-symmetry of operators. As a consequence of our work, we show that any smooth compact operator defined on a smooth and reflexive Banach space is either a…

Functional Analysis · Mathematics 2024-09-20 Divya Khurana

It is shown that an elliptic scattering operator $A$ on a compact manifold with boundary with coefficients in the bounded operators of a bundle of Banach spaces of class (HT) and Pisier's property $(\alpha)$ has maximal regularity (up to a…

Analysis of PDEs · Mathematics 2007-05-23 Robert Denk , Thomas Krainer