Search results for " conjectur"

Noetherian type in topological products

2010

The cardinal invariant "Noetherian type" of a topological space $X$ (Nt(X)) was introduced by Peregudov in 1997 to deal with base properties that were studied by the Russian School as early as 1976. We study its behavior in products and box-products of topological spaces. We prove in Section 2: 1) There are spaces $X$ and $Y$ such that $Nt(X \times Y) < \min\{Nt(X), Nt(Y)\}$. 2) In several classes of compact spaces, the Noetherian type is preserved by the operations of forming a square and of passing to a dense subspace. The Noetherian type of the Cantor Cube of weight $\aleph_\omega$ with the countable box topology, $(2^{\aleph_\omega})_\delta$, is shown in Section 3 to be closely related …

Exact constants in Poincaré type inequalities for functions with zero mean boundary traces

2014

In this paper, we investigate Poincare type inequalities for the functions having zero mean value on the whole boundary of a Lipschitz domain or on a measurable part of the boundary. We find exact and easily computable constants in these inequalities for some basic domains (rectangles, cubes, and right triangles) and discuss applications of the inequalities to quantitative analysis of partial differential equations. Copyright © 2014 John Wiley & Sons, Ltd.

Conway irreducible hyperbolic knots with two common covers

2005

International audience; For each pair of coprime integers n > m ≥ 2 we construct pairs of non equivalent Conway irreducible hyperbolic knots with the same n-fold and m-fold cyclic branched covers.

Harmonic balance analysis of pull-in range and oscillatory behavior of third-order type 2 analog PLLs

2020

The most important design parameters of each phase-locked loop (PLL) are the local and global stability properties, and the pull-in range. To extend the pull-in range, engineers often use type 2 PLLs. However, the engineering design relies on approximations which prevent a full exploitation of the benefits of type 2 PLLs. Using an exact mathematical model and relying on a rigorous mathematical thinking this problem is revisited here and the stability and pull-in properties of the third-order type 2 analog PLLs are determined. Both the local and global stability conditions are derived. As a new idea, the harmonic balance method is used to derive the global stability conditions. That approach…

Per una nuova edizione critica di Curzio Rufo (1)

2009

On the Landis conjecture for the fractional Schrödinger equation

2023

In this paper, we study a Landis-type conjecture for the general fractional Schrödinger equation ((−P)s+q)u=0. As a byproduct, we also prove the additivity and boundedness of the linear operator (−P)s for non-smooth coefficents. For differentiable potentials q, if a solution decays at a rate exp (−∣x∣1+), then the solution vanishes identically. For non-differentiable potentials q, if a solution decays at a rate exp (−∣x∣4s−14s+), then the solution must again be trivial. The proof relies on delicate Carleman estimates. This study is an extension of the work by Rüland and Wang (2019). peerReviewed

UNIQUELY HAMILTONIAN GRAPHS. A TALK IN THREE PARTS

2018

Professor of UWA Gordon Royle gives a talk in Singapour devoted to UH3 graphs, graphs with unique Hamiltonian cycle with vertex degree at least three

Using 2-colorings in the theory of uniquely Hamiltonian graphs

2019

We use the concept of 2-coloring in analyzing UH3 graphs and building exact specifications of functions to find new UH3 graphs by Hamiltonian cycle edge extractions

Il senso e il futuro della coscienza individuale nella metafisica di Piero Martinetti

2018

L'articolo intende analizzare la posizione di Martinetti sulla sopravvivenza dell'anima individuale dopo la morte, così come si presenta nella sua metafisica e alla luce della sua principale fonte di ispirazione, individuata nella filosofia di Plotino. Martinetti mostra come il rapporto tra unità e molteplicità si presenti nell'uomo in due diverse e complementari prospettive: come una fondamentale identità nella dimensione intemporale della vita intelligibile dello spirito, e come una tensione dinamica nell'ordine empirico del divenire spazio-temporale. Entrambe queste dimensioni si esprimono finalisticamente, attratte dall’Uno che opera in loro come potenza di armonizzazione e raccogliment…

Radial symmetry of p-harmonic minimizers

2017

"It is still not known if the radial cavitating minimizers obtained by Ball [J.M. Ball, Discontinuous equilibrium solutions and cavitation in nonlinear elasticity, Phil. Trans. R. Soc. Lond. A 306 (1982) 557--611] (and subsequently by many others) are global minimizers of any physically reasonable nonlinearly elastic energy". The quotation is from [J. Sivaloganathan and S. J. Spector, Necessary conditions for a minimum at a radial cavitating singularity in nonlinear elasticity, Ann. Inst. H. Poincare Anal. Non Lineaire 25 (2008), no. 1, 201--213] and seems to be still accurate. The model case of the $p$-harmonic energy is considered here. We prove that the planar radial minimizers are indee…