Results 41 to 50 of about 726,333 (182)

A simple proof of the invariant torus theorem [PDF]

, 2010
We give a simple proof of Kolmogorov's theorem on the persistence of a quasiperiodic invariant torus in Hamiltonian systems. The theorem is first reduced to a well-posed inversion problem (Herman's normal form) by switching the frequency obstruction from
Féjoz, Jacques
core   +3 more sources

Oscillation of solutions to fourth-order trinomial delay differential equations

Electronic Journal of Differential Equations, 2015
The objective of this article is to study the oscillation properties of the solutions to the fourth-order linear trinomial delay differential equation $$ y^{(4)}(t)+p(t)y'(t)+q(t)y(\tau(t))=0.
Jozef Dzurina, Blanka Baculikova, Irena Jadlovska   +2 more
doaj  

Addendum to Methods of extending lower order problems to higher order problems in the context of smallest eigenvalue comparisons

Electronic Journal of Qualitative Theory of Differential Equations, 2012
This paper serves as an addendum to the paper titled Methods of extending lower order problems to higher order problems in the context of smallest eigenvalue comparisons appearing in EJQTDE no. 99, 2011.
Jeffrey Neugebauer
doaj   +1 more source

A comparison theorem for backward SPDEs with jumps

, 2014
In this paper we obtain a comparison theorem for backward stochastic partial differential equation (SPDEs) with jumps. We apply it to introduce space-dependent convex risk measures as a model for risk in large systems of interacting ...
Sulem, Agnès, Zhang, Tusheng, Øksendal, Bernt   +2 more
core   +2 more sources

Dynamic behaviors of a nonautonomous predator–prey system with Holling type II schemes and a prey refuge

Advances in Difference Equations, 2021
In this paper, we consider a nonautonomous predator–prey model with Holling type II schemes and a prey refuge. By applying the comparison theorem of differential equations and constructing a suitable Lyapunov function, sufficient conditions that ...
Yumin Wu, Fengde Chen, Caifeng Du
doaj   +1 more source

A Comparison Theorem for Eigenfunctions [PDF]

Proceedings of the American Mathematical Society, 1973
A comparison theorem of Sturm's type is obtained for eigenfunctions of general linear elliptic partial differential operators of second order on bounded domains of n-dimensional Euclidean space. The proof is almost immediate from an earlier identity of the author. The theorem is shown to be stronger than some recent theorems of Kurt Kreith.
openaire   +1 more source

Investigation of the Oscillatory Properties of Fourth-Order Delay Differential Equations Using a Comparison Approach with First- and Second-Order Equations

Axioms
This paper investigates the oscillatory behavior of solutions to fourth-order functional differential equations (FDEs) with multiple delays and a middle term.
Osama Moaaz, Shaimaa Elsaeed, Asma Al-Jaser, Samia Ibrahim, Amira Essam   +4 more
doaj   +1 more source

A Note on Comparison Theorems [PDF]

Proceedings of the American Mathematical Society, 1977
Comparison theorems for solutions, for focal points and conjugate points of second order linear differential equations are given in this paper.
openaire   +1 more source

LOGARITHMIC DE RHAM COMPARISON FOR OPEN RIGID SPACES

Forum of Mathematics, Sigma, 2019
In this note, we prove the logarithmic $p$-adic comparison theorem for open rigid analytic varieties. We prove that a smooth rigid analytic variety with a strict simple normal crossing divisor is locally $K(\unicode[STIX]{x1D70B},1)$ (in a certain sense)
SHIZHANG LI, XUANYU PAN
doaj   +1 more source

On the Curvature and Heat Flow on Hamiltonian Systems

Analysis and Geometry in Metric Spaces, 2014
We develop the differential geometric and geometric analytic studies of Hamiltonian systems. Key ingredients are the curvature operator, the weighted Laplacian, and the associated Riccati equation.We prove appropriate generalizations of the Bochner ...
Ohta Shin-ichi
doaj   +1 more source