Results 11 to 20 of about 4,824 (216)
Ideal-quasi-Cauchy sequences [PDF]
An ideal $I$ is a family of subsets of positive integers $\textbf{N}$ which is closed under taking finite unions and subsets of its elements.
Cakalli, Huseyin, Hazarika, Bipan
core +2 more sources
A bounded consistency theorem for strong summabilities
The study of R-type summability methods is continued in this paper by showing that two such methods are identical on the bounded portion of the strong summability field associated with the methods.
C. S. Chun, A. R. Freedman
doaj +1 more source
Summability Methods for Oscillation of Linear Second-Order Matrix Differential Equations
The oscillation criteria of Wintner and Hartman for the equation \(Y''+ q(t)y=0\) on \([0,\infty)\) using limits of the mean \((1/t)\int^ t_ 0\left(\int^ s_ 0 q(u)du\right)ds\) have been extended in many ways. Other extensions of the scalar results have been made to the matrix equation \(Y''+ Q(t)= 0\) and to the selfadjoint matrix equation (1) \((PY')'
Coles, William J., Kinyon, Michael K.
openaire +3 more sources
Summability methods based on the Riemann Zeta function
This paper is a study of summability methods that are based on the Riemann Zeta function. A limitation theorem is proved which gives a necessary condition for a sequence x to be zeta summable.
Larry K. Chu
doaj +1 more source
Resumming the string perturbation series [PDF]
We use the AdS/CFT correspondence to study the resummation of a perturbative genus expansion appearing in the type II superstring dual of ABJM theory.
Grassi, Alba +2 more
core +3 more sources
We prove the necessary and sufficient conditions for an infinity matrix to be a mapping, from absolutely convergent series to convergent sequences, which is treated as general weighted mean summability methods.
Jinlu Li
doaj +1 more source
Approximation of Analytic Functions by Universal Vallee-Poussin Sums on the Chebyshev Polynomials
As it is known, Chebyshev polynomials provide the best uniform approach of a function. They are a special case of Faber polynomials. A. I. Shvay (1973) proved that the Vallee-Poussin sums are the best approach apparatus in comparison with the partial ...
L.K. Dodunova, A.A. Ageikin
doaj +1 more source
Approximation of high-dimensional parametric PDEs [PDF]
Parametrized families of PDEs arise in various contexts such as inverse problems, control and optimization, risk assessment, and uncertainty quantification. In most of these applications, the number of parameters is large or perhaps even infinite.
Cohen, Albert, Devore, Ronald
core +4 more sources
Uniqueness of the Fock quantization of scalar fields in spatially flat cosmological spacetimes [PDF]
We study the Fock quantization of scalar fields in (generically) time dependent scenarios, focusing on the case in which the field propagation occurs in --either a background or effective-- spacetime with spatial sections of flat compact topology.
Blas, Daniel Martín-de +4 more
core +3 more sources
Constructive Field Theory in Zero Dimension
In this pedagogical note we propose to wander through five different methods to compute the number of connected graphs of the zero-dimensional $\phi^4$ field theory,in increasing order of sophistication.
Rivasseau, V.
core +5 more sources

