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441.
In the present paper, we consider a class of strong resonance problems for nonlinear elliptic Neumann BVPs, and establish existence and multiplicity results for positive, negative and sign-changing solutions by using a Morse theoretical approach. 相似文献
442.
Two-dimensional discrete breathers in a two-dimensional Morse lattice with on-site harmonic potentials are investigated. Under the harmonic approximation, the linear dispersion relations for the triangular and the square lattices are discussed. The existence of discrete breathers in a two-dimensional Morse lattice with on-site harmonic potentials is proved by using local inharmonic approximation and the numerical method. The localization and amplitude of two-dimensional discrete breathers correlate closely to the Morse parameter a and the on-site parameter κ. 相似文献
443.
444.
S Miraboutalebi 《中国物理 B》2016,25(10):100301-100301
We investigate an analytical solution for the Schr o¨dinger equation with a position-dependent mass distribution, with the Morse potential via Laplace transformations. We considered a mass function localized around the equilibrium position.The mass distribution depends on the energy spectrum of the state and the intrinsic parameters of the Morse potential. An exact bound state solution is obtained in the presence of this mass distribution. 相似文献
445.
Binding energy of the donor impurities in GaAs-Ga_(1-x)Al_xAs quantum well wires with Morse potential in the presence of electric and magnetic fields 下载免费PDF全文
The behavior of a donor in the GaAs–Ga_(1-x)Al_xAs quantum well wire represented by the Morse potential is examined within the framework of the effective-mass approximation. The donor binding energies are numerically calculated for with and without the electric and magnetic fields in order to show their influence on the binding energies. Moreover, how the donor binding energies change for the constant potential parameters(De, re, and a) as well as with the different values of the electric and magnetic field strengths is determined. It is found that the donor binding energy is highly dependent on the external electric and magnetic fields as well as parameters of the Morse potential. 相似文献
446.
Tom Braden 《Proceedings of the American Mathematical Society》2002,130(7):2037-2043
We show that some monodromies in the Morse local systems of a conically stratified perverse sheaf imply that other Morse local systems for smaller strata do not vanish. This result is then used to explain the examples of reducible characteristic varieties of Schubert varieties given by Kashiwara and Saito in type and by Boe and Fu for the Lagrangian Grassmannian.
447.
Given a smooth closed manifold M, the Morse–Witten complex associated to a Morse function f and a Riemannian metric g on M consists of chain groups generated by the critical points of f and a boundary operator counting isolated flow lines of the negative gradient flow. Its homology reproduces singular homology of M. The geometric approach presented here was developed in Weber [Der Morse–Witten Komplex, Diploma Thesis, TU Berlin, 1993] and is based on tools from hyperbolic dynamical systems. For instance, we apply the Grobman–Hartman theorem and the λ-lemma (Inclination Lemma) to analyze compactness and define gluing for the moduli space of flow lines. 相似文献
448.
Alfonso Castro Mó nica Clapp 《Proceedings of the American Mathematical Society》2006,134(1):167-175
We establish upper bounds for the energy of critical levels of the functional associated to a perturbed superlinear elliptic boundary value problem. We show that the perturbed problem satisfies the estimates obtained by Bahri and Lions (1988) for the symmetric problem. We use these estimates to prove the existence of nonradial solutions to a radial elliptic boundary value problem. Our results fill a gap in an earlier paper by Aduén and Castro.
449.
In this paper we study the existence of multiple nontrivial solutions for a semilinear elliptic equation at resonance by the minimax methods and Morse theory. 相似文献
450.
We show how a simplicial complex arising from the WDVV (Witten-Dijkgraaf-Verlinde-Verlinde) equations of string theory is
the Whitehouse complex. Using discrete Morse theory, we give an elementary proof that the Whitehouse complex Δn is homotopy equivalent to a wedge of (n−2)! spheres of dimension n−4. We also verify the Cohen-Macaulay property. Additionally, recurrences are given for the face enumeration of the complex
and the Hilbert series of the associated pre-WDVV ring.
2000 Mathematics Subject Classification: Primary—13F55, Secondary—05E99, 55P15 相似文献