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The attracting set and the inverse limit set are important objects associated to a self-map on a set. We call \emph{stable set} of the self-map the projection of the inverse limit set. It is included in the attracting set, but is not equal…

Group Theory · Mathematics 2009-09-22 Eddy Godelle

In this paper we describe invariant geometrical ~structures in the phase space of the Swift-Hohenberg equation in a neighborhood of its periodic stationary states. We show that in spite of the fact that these states are only marginally…

patt-sol · Physics 2009-10-30 J. -P. Eckmann , C. E. Wayne , P. Wittwer

We consider a self-adjoint operator $T$ on a separable Hilbert space, with pure-point and simple spectrum with accumulations at finite points. Explicit conditions are stated on the eigenvalues of $T$ and on the bounded perturbation $V$…

Mathematical Physics · Physics 2024-03-06 Paolo Facchi , Marilena Ligabò

In this paper, we consider the problem of choosing a set of multi-party contracts, where each coalition of agents has a non-empty finite set of contracts to choose from. We call such problems, contract choice problems. We provide conditions…

Optimization and Control · Mathematics 2007-05-23 Somdeb Lahiri

Kazhdan constants of discrete groups are hard to compute and the actual constants are known only for several classes of groups. By solving a semidefinite programming problem by a computer, we obtain a lower bound of the Kazhdan constant of…

Group Theory · Mathematics 2017-03-23 Koji Fujiwara , Yuichi Kabaya

Open quantum systems weakly coupled to the environment are modeled by completely positive, trace preserving semigroups of linear maps. The generators of such evolutions are called Lindbladians. In the setting of quantum many-body systems on…

Quantum Physics · Physics 2015-04-29 Toby S. Cubitt , Angelo Lucia , Spyridon Michalakis , David Perez-Garcia

Many statistical estimators are defined as the fixed point of a data-dependent operator, with estimators based on minimizing a cost function being an important special case. The limiting performance of such estimators depends on the…

Machine Learning · Computer Science 2022-03-22 Nhat Ho , Koulik Khamaru , Raaz Dwivedi , Martin J. Wainwright , Michael I. Jordan , Bin Yu

Recent results in the literature provide computational evidence that stabilized semi-implicit time-stepping method can efficiently simulate phase field problems involving fourth-order nonlinear dif- fusion, with typical examples like the…

Numerical Analysis · Mathematics 2016-06-22 Dong Li , Zhonghua Qiao , Tao Tang

We present a model for spectral theory of families of selfadjoint operators, and their corresponding unitary one-parameter groups (acting in Hilbert space.) The models allow for a scale of complexity, indexed by the natural numbers…

Spectral Theory · Mathematics 2012-02-21 Palle Jorgensen , Steen Pedersen , Feng Tian

In this paper we study stable finiteness of ample groupoid algebras with applications to inverse semigroup algebras and Leavitt path algebras, recovering old results and proving some new ones. In addition, we develop a theory of (faithful)…

Rings and Algebras · Mathematics 2025-10-24 Benjamin Steinberg

We define a numerical quasi-isometry invariant of a finitely generated group, whose values parametrize the difference between the group being uniformly embeddable in a Hilbert space and the reduced C*-algebra of the group being exact.

Operator Algebras · Mathematics 2007-05-23 Erik Guentner , Jerome Kaminker

When the singular values of the evolution operator are all smaller or all greater than one, stable integration algorithms are obtained either by explicit or implicit methods. When the singular spectrum mixes greater and smaller than one…

Plasma Physics · Physics 2021-01-19 João P. S. Bizarro , L. Venâncio , R. Vilela Mendes

We start up the study of the stability of general graph pairs. This notion is a generalization of the concept of the stability of graphs. We say that a pair of graphs $(\Gamma,\Sigma)$ is stable if $Aut(\Gamma\times\Sigma) \cong…

Combinatorics · Mathematics 2020-11-02 Yan-Li Qin , Binzhou Xia , Jin-Xin Zhou , Sanming Zhou

We show how the state of an unstable particle can be defined in terms of stable asymptotic states. This general definition is used to discuss and to solve some old problems connected with the short-time and large-time behaviour of the…

High Energy Physics - Theory · Physics 2009-10-30 L. Maiani , M. Testa

We show a general relation between fixed point stability of suitably perturbed transfer operators and convergence to equilibrium (a notion which is strictly related to decay of correlations). We apply this relation to deterministic…

Dynamical Systems · Mathematics 2016-07-19 Stefano Galatolo

A provably stable summation-by-parts simultaneous approximation term (SBP-SAT) finite-difference time-domain (FDTD) subgridding method without region split is proposed. By designing projection SBP operators tailored for embedded topological…

Computational Engineering, Finance, and Science · Computer Science 2026-04-17 Yuhui Wang , Langran Deng , Weibo Wu , Hanhong Liu , Xinyue Zhang , Xingqi Zhang , Jian Wang , Wei-Jie Wang , Zhizhang Chen , Shunchuan Yang

We study conditions for the existence of stable and group-strategy-proof mechanisms in a many-to-one matching model with contracts if students' preferences are monotone in contract terms. We show that "equivalence", properly defined, to a…

Theoretical Economics · Economics 2021-07-13 Jan Christoph Schlegel

The $\mathbf{k \cdot p}$ method is a successful approach to obtain band structure, optical and transport properties of semiconductors, and it depends on external parameters that are obtained either from experiments, tight binding or ab…

This work studies the symmetries, the associated momentum map, and relative equilibria of a mechanical system consisting of a small axisymmetric magnetic body-dipole in an also axisymmetric external magnetic field that additionally exhibits…

Symplectic Geometry · Mathematics 2013-11-12 Lyudmila Grigoryeva , Juan-Pablo Ortega , Stanislav Zub

The goal of this paper is to investigate the stability of the Helmholtz equation in the high- frequency regime with non-smooth and rapidly oscillating coefficients on bounded domains. Existence and uniqueness of the problem can be proved…

Numerical Analysis · Mathematics 2018-11-14 Stefan Sauter , Celine Torres