Results 21 to 30 of about 109,954 (249)
Analysis of non scalar control problems for parabolic systems by the block moment method
Comptes Rendus. Mathématique, 2023 This article deals with abstract linear time invariant controlled systems of parabolic type. In [9], with A. Benabdallah, we introduced the block moment method for scalar control operators.
Boyer, Franck, Morancey, Morgan
doaj +1 more source
Boolean algebras of projections and resolutions of the identity of scalar-type spectral operators [PDF]
Proceedings of the Edinburgh Mathematical Society, 1997 Let Μ be a Bade complete (or σ-complete) Boolean algebra of projections in a Banach space X. This paper is concerned with the following questions: When is Μ equal to the resolution of the identity (or the strong operator closure of the resolution of the identity) of some scalar-type spectral operator T (with σ(T) ⊆ ℝ) in X?
B. Pagter, W. Ricker
semanticscholar +3 more sources
The mixed Yamabe problem for harmonic foliations [PDF]
, 2015 The mixed scalar curvature of a foliated Riemannian manifold, i.e., an averaged mixed sectional curvature, has been considered by several geometers. We explore the Yamabe type problem: to prescribe the constant mixed scalar curvature for a foliation by a
Rovenski, Vladimir, Zelenko, Leonid
core +1 more source
Spinning AdS Loop Diagrams: Two Point Functions [PDF]
, 2018 We develop a systematic approach to evaluating AdS loop amplitudes based on the spectral (or "split") representation of bulk-to-bulk propagators, which re-expresses loop diagrams in terms of spectral integrals and higher-point tree diagrams. In this work
Giombi, Simone +2 more
core +2 more sources
On the Non-Hypercyclicity of Normal Operators, Their Exponentials, and Symmetric Operators
Mathematics, 2019 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 e t A t ≥ 0 of its exponentials, which, under a certain ...
Marat V. Markin, Edward S. Sichel
doaj +1 more source
A Dark Sector Extension of the Almost-Commutative Standard Model [PDF]
, 2013 We consider an extension of the Standard Model within the frame work of Noncommutative Geometry. The model is based on an older model [St09] which extends the Standard Model by new fermions, a new U(1)-gauge group and, crucially, a new scalar field which
Stephan, Christoph A.
core +1 more source
Gravitational and axial anomalies for generalized Euclidean Taub-NUT metrics [PDF]
, 2004 The gravitational anomalies are investigated for generalized Euclidean Taub-NUT metrics which admit hidden symmetries analogous to the Runge-Lenz vector of the Kepler-type problem. In order to evaluate the axial anomalies, the index of the Dirac operator
Atiyah M F +21 more
core +1 more source
OPERATOR METHOD IN THE SCALAR WAVE DIFFRACTION BY AXIALLY-SYMMETRIC DISCONTINUITIES IN THE SCREEN
Radio Physics and Radio Astronomy, 2018 Purpose: The scalar wave diffraction by the annular slot in an infinitely thin screen is considered in case of Dirichlet and Neumann boundary conditions. Diffraction problem by a flat ring is also considered as a dual one.
M. E. Kaliberda +2 more
doaj +1 more source
Properties which normal operators share with normal derivations and related operators [PDF]
, 1975 Let $S$ and $T$ be (bounded) scalar operators on a Banach space $\scr X$ and let $C(T,S)$ be the map on $\scr B(\scr X)$, the bounded linear operators on $\scr X$, defined by $C(T,S)(X)=TX-XS$ for $X$ in $\scr B(\scr X)$.
Ciprian Poia, Joel Anderson, Let S
core +1 more source
Bounds for OPE coefficients on the Regge trajectory
Journal of High Energy Physics, 2017 We consider the Regge limit of the CFT correlation functions JJOO $$ \left\langle \mathcal{JJOO}\right\rangle $$ and T T O O $$ \left\langle TT\mathcal{O}\mathcal{O}\right\rangle $$ , where J $$ \mathcal{J} $$ is a vector current, T is the stress tensor ...
Miguel S. Costa +2 more
doaj +1 more source