Homoclinic solutions of some second order non-autonomous systems

In this paper we investigate the existence of homoclinic solutions for the following second order non-autonomous system

where A is an antisymmetric constant matrix, is a symmetric and positive definite matrix for all , W(t,q)=a(t)V(q) such that is a continuous function and . Assuming that V(q) is subquadratic as q→+∞ and some technical assumptions on A and L, we establish two existence criteria to guarantee that (DS) has at least one nontrivial homoclinic solution by using a standard minimizing argument. Besides that, in some particular case, for the first time the uniqueness of homoclinic solutions of (DS) is also obtained. Recent results in the literature are generalized and significantly improved.     

Periodic solutions of second order non-autonomous Hamiltonian systems with local superquadratic potential

Some existence theorems are obtained for periodic solutions of a class of non-autonomous second order Hamiltonian systems with local superquadratic potential, by making use of the generalized mountain pass theorem.     

非自治二阶Hamilton系统的周期解

本文推广了Willem的一个结果,Willem研究的受迫周期振动要求受迫势能关于空间变量是周期的,而本文只要求受迫势能对时间变量积分后关于空间变量是周期的,该结果包括了单摆的受迫振动.本文将用直接变分最小方法和Rabinowtz的鞍点定理来研究当势函数对时间变量积分后是周期时受迫摆方程的周期解.     

Periodic solutions of non-autonomous second order Hamiltonian systems

The purpose of this paper is to study the existence of periodic solutions for a class of non-autonomous second order Hamiltonian system. Some new existence theorems are obtained by the least action principle.     

Homoclinic solutions for a class of second order Hamiltonian systems

In this paper, we study homoclinic solutions for the nonperiodic second order Hamiltonian systems where L is unnecessarily coercive or uniformly positively definite, and is only locally defined near the origin with respect to u. Under some general conditions on L and W, we show that the above system has infinitely many homoclinic solutions near the origin. Some related results in the literature are extended and generalized.     

Homoclinic solutions for a class of the second order Hamiltonian systems

We study the existence of homoclinic orbits for the second order Hamiltonian system , where q∈Rⁿ and V∈C¹(R×Rⁿ,R), V(t,q)=-K(t,q)+W(t,q) is T-periodic in t. A map K satisfies the “pinching” condition b₁|q|²?K(t,q)?b₂|q|², W is superlinear at the infinity and f is sufficiently small in L²(R,Rⁿ). A homoclinic orbit is obtained as a limit of 2kT-periodic solutions of a certain sequence of the second order differential equations.     

Periodic solutions for a class of new superquadratic second order Hamiltonian systems

A new superquadratic growth condition is introduced, which is an extension of the well-known superquadratic growth condition due to P.H. Rabinowitz and the nonquadratic growth condition due to Gui-Hua Fei. An existence theorem is obtained for periodic solutions of a class of new superquadratic second order Hamiltonian systems by the minimax methods in critical point theory, specially, a local linking theorem.     

Fast homoclinic solutions for some second order non-autonomous systems

This paper is concerned with the existence of homoclinic solutions for the following second order non-autonomous system

(FHS)     

Homoclinic solutions for a class of second order discrete Hamiltonian systems

Consider the second order discrete Hamiltonian systems Δ2u(n-1)-L(n)u(n) + ▽W (n, u(n)) = f(n),where n ∈ Z, u ∈ RN and W : Z × RN → R and f : Z → RN are not necessarily periodic in n. Under some comparatively general assumptions on L, W and f , we establish results on the existence of homoclinic orbits. The obtained results successfully generalize those for the scalar case.     

New existence of periodic solutions for second order non-autonomous Hamiltonian systems

By using mountain pass theorem and local link theorem, some existence theorems are obtained for periodic solutions of second order non-autonomous Hamiltonian systems under local superquadratic condition and other suitable conditions.     

Periodic solutions of a class of superquadratic second order Hamiltonian systems

§1　IntroductionInthispaperwediscusstheexistenceofthesolutionforthefollowingsecondorderHamiltoniansystemx¨ Ax ΔF(x)=0,(1.1)whereAisann×nrealsymmetricmatrixandisnon-definite,F∈C1(Rn,R),andΔF(x)denotesthegradientofF.WhileworksforsecondorderHamiltonsystemshavemostlybeendoneundertheconditionA=0,westudythecasewhereA≠0andisnon-definiteinthepapers[1,2].DefineH=H1,2T([0,T],Rn)={x:R→Rn|xisabsolutelycontinuous,x∈L2([0,T],Rn),x(0)=x(T),x(0)=x(T)}and〈x,y〉=∫T0[(x(t),y(t)) (x…     

Subharmonic and homoclinic solutions for second order Hamiltonian systems with new superquadratic conditions

The existence of infinitely many subharmonic solutions is obtained for a class of nonautonomous second order Hamiltonian systems with a new superquadratic condition. Furthermore, we can get the existence of homoclinic solutions as the limit of subharmonics under a stronger superquadratic condition which is still weaker than the growth conditions in the references.     

Homoclinic solutions for second order impulsive Hamiltonian systems with small forcing terms

In this paper, we establish some new sufficient conditions on the existence of homoclinic solution for a class of second‐order impulsive Hamiltonian systems. By using the mountain pass theorem, we demonstrate that the limit of a 2kT‐periodic approximation solution is a homoclinic solution of our problem. We also present some examples to illustrate the applications of our main results. Copyright © 2016 John Wiley & Sons, Ltd.     

Periodic solutions for some nonautonomous second order Hamiltonian systems

The existence and multiplicity of periodic solutions are obtained for nonautonomous second order Hamiltonian systems by the minimax methods in critical point theory.     

Periodic solutions of a class of second order non-autonomous Hamiltonian systems

Some existence theorems are obtained for periodic solutions of non-autonomous second order systems by using the least action principle and minimax methods in critical point theory. Our results extend and improve many previously known results.