Search results for " solution"

showing 10 items of 3084 documents

Nonlinear scalar field equations with general nonlinearity

2018

Consider the nonlinear scalar field equation \begin{equation} \label{a1} -\Delta{u}= f(u)\quad\text{in}~\mathbb{R}^N,\qquad u\in H^1(\mathbb{R}^N), \end{equation} where $N\geq3$ and $f$ satisfies the general Berestycki-Lions conditions. We are interested in the existence of positive ground states, of nonradial solutions and in the multiplicity of radial and nonradial solutions. Very recently Mederski [30] made a major advance in that direction through the development, in an abstract setting, of a new critical point theory for constrained functionals. In this paper we propose an alternative, more elementary approach, which permits to recover Mederski's results on the scalar field equation. T…

Pure mathematicsMathematics::Analysis of PDEsMonotonic function2010 MSC: 35J20 35J6001 natural sciencesMathematics - Analysis of PDEsFOS: Mathematics[MATH.MATH-AP]Mathematics [math]/Analysis of PDEs [math.AP]Mountain pass0101 mathematicsMathematicsgeographygeography.geographical_feature_category35J20 35J60Applied Mathematics010102 general mathematicsMultiplicity (mathematics)Monotonicity trickNonradial solutions010101 applied mathematicsNonlinear systemBerestycki-Lions nonlinearityBounded functionNonlinear scalar field equationsScalar fieldAnalysisAnalysis of PDEs (math.AP)
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Continuous numerical solutions of coupled mixed partial differential systems using Fer's factorization

1999

In this paper continuous numerical solutions expressed in terms of matrix exponentials are constructed to approximate time-dependent systems of the type ut A(t)uxx B(t)u=0; 0 0, u(0;t)=u(p;t)=0; u(x;0)=f(x);06 x6p. After truncation of an exact series solution, the numerical solution is constructed using Fer’s factorization. Given >0 and t0;t1; with 0<t0<t1 and D(t0;t1)=f(x;t); 06x6p; t06t6t1g the error of the approximated solution with respect to the exact series solution is less than uniformly in D(t0;t1). An algorithm is also included. c 1999 Elsevier Science B.V. All rights reserved. AMS classication: 65M15, 34A50, 35C10, 35A50

Pure mathematicsPartial differential equationSeries (mathematics)TruncationApplied MathematicsMixed time-dependent partial differential systemsType (model theory)Fer's factorizationExponential functionAlgorithmCombinatoricsComputational MathematicsMatrix (mathematics)Accurate solutionFactorizationPartial derivativeA priori error boundsMathematicsJournal of Computational and Applied Mathematics
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Nonexistence of global weak solutions for a nonlinear Schrodinger equation in an exterior domain

2020

We study the large-time behavior of solutions to the nonlinear exterior problem L u ( t , x ) = &kappa

Pure mathematicsPhysics and Astronomy (miscellaneous)General MathematicsGlobal weak solution01 natural sciencesDomain (mathematical analysis)symbols.namesakeSettore MAT/05 - Analisi MatematicaComputer Science (miscellaneous)Neumann boundary conditionNonlinear Schrödinger equationBall (mathematics)0101 mathematicsNonlinear Schrödinger equationPhysicsComplex-valued functionOpen unitOperator (physics)lcsh:Mathematics010102 general mathematicsUnit normal vectorlcsh:QA1-939010101 applied mathematicsMathematics::LogicChemistry (miscellaneous)symbolsExterior domainNonhomegeneous Neumann boundary condition
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Fixed Points for Multivalued Weighted Mean Contractions in a Symmetric Generalized Metric Space

2020

This paper defines two new concepts: the concept of multivalued left-weighted mean contractions in the generalized sense of Nadler in a symmetric generalized metric space and the concept of multivalued right-weighted mean contractions in the generalized sense of Nadler in a symmetric generalized metric space, and demonstrates fixed-point theorems for them. For these, we demonstrated two fixed-point existence theorems and their corollaries, by using the properties of the regular-global-inf function and the properties of symmetric generalized metric spaces, respectively. Moreover, we demonstrated that the theorems can be applied in particular cases of inclusion systems. This article contains …

Pure mathematicsPhysics and Astronomy (miscellaneous)multivalued left-weighted mean contractionGeneral Mathematicslcsh:Mathematicsfixed points010102 general mathematicsFunction (mathematics)Fixed pointlcsh:QA1-93901 natural sciences010101 applied mathematicsMetric spaceChemistry (miscellaneous)Computer Science (miscellaneous)In real lifeOrder (group theory)0101 mathematicsEquilibrium solutionWeighted arithmetic meanmultivalued right-weighted mean contractionregular-global-inf functionMathematicsSymmetry
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Positive solutions for the Neumann p-Laplacian

2017

We examine parametric nonlinear Neumann problems driven by the p-Laplacian with asymptotically ( $$p-1$$ )-linear reaction term f(z, x) (as $$x\rightarrow +\infty $$ ). We determine the existence, nonexistence and minimality of positive solutions as the parameter $$\lambda >0$$ varies.

Pure mathematicsPositive solutions Nonlinear regularity Nonlinear maximum principle Nonlinear Picone’s identityGeneral Mathematics010102 general mathematicsMathematical analysisLambda01 natural sciencesTerm (time)010101 applied mathematicsNonlinear systemSettore MAT/05 - Analisi Matematicap-Laplacian0101 mathematicsParametric statisticsMathematics
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Perturbed eigenvalue problems for the Robin p-Laplacian plus an indefinite potential

2020

AbstractWe consider a parametric nonlinear Robin problem driven by the negativep-Laplacian plus an indefinite potential. The equation can be thought as a perturbation of the usual eigenvalue problem. We consider the case where the perturbation$$f(z,\cdot )$$f(z,·)is$$(p-1)$$(p-1)-sublinear and then the case where it is$$(p-1)$$(p-1)-superlinear but without satisfying the Ambrosetti–Rabinowitz condition. We establish existence and uniqueness or multiplicity of positive solutions for certain admissible range for the parameter$$\lambda \in {\mathbb {R}}$$λ∈Rwhich we specify exactly in terms of principal eigenvalue of the differential operator.

Pure mathematicsSublinear functionPerturbation (astronomy)Sublinear and superlinear perturbationLambda01 natural sciencesNonlinear Picone’s identitySettore MAT/05 - Analisi MatematicaUniqueness0101 mathematicsMathematical PhysicsEigenvalues and eigenvectorsPositive solutionsMathematicsNonlinear regularityAlgebra and Number TheoryMinimal positive solution010102 general mathematicsDifferential operator010101 applied mathematicsNonlinear systemp-LaplacianIndefinite potentialUniquenessNonlinear maximum principleAnalysis
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Multiple solutions for nonlinear nonhomogeneous resonant coercive problems

2018

We consider a nonlinear, nonhomogeneous Dirichlet problem driven by the sum of a \begin{document}$p$\end{document} -Laplacian ( \begin{document}$2 ) and a Laplacian. The reaction term is a Caratheodory function \begin{document}$f(z,x)$\end{document} which is resonant with respect to the principal eigenvalue of ( \begin{document}$-\Delta_p,\, W^{1,p}_0(\Omega)$\end{document} ). Using variational methods combined with truncation and comparison techniques and Morse theory (critical groups) we prove the existence of three nontrivial smooth solutions all with sign information and under three different conditions concerning the behavior of \begin{document}$f(z,\cdot)$\end{document} near zero. By …

Pure mathematicsTruncation01 natural sciencesResonanceExtremal constant sign solutionConstant sign and nodal solutionDiscrete Mathematics and Combinatorics0101 mathematicsEigenvalues and eigenvectorsCritical groupDiscrete Mathematics and CombinatoricMorse theoryNonlinear regularityPhysicsDirichlet problemMultiple smooth solutionComputer Science::Information RetrievalApplied Mathematics010102 general mathematicsZero (complex analysis)AnalysiFunction (mathematics)010101 applied mathematicsLaplace operatorAnalysisSign (mathematics)
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Riesz and Wolff potentials and elliptic equations in variable exponent weak Lebesgue spaces

2015

Submitted by Alexandre Almeida (jaralmeida@ua.pt) on 2015-11-12T11:41:07Z No. of bitstreams: 1 RieszWolff_RIA.pdf: 159825 bytes, checksum: d99abdf3c874f47195619a31ff5c12c7 (MD5) Approved for entry into archive by Bella Nolasco(bellanolasco@ua.pt) on 2015-11-17T12:18:41Z (GMT) No. of bitstreams: 1 RieszWolff_RIA.pdf: 159825 bytes, checksum: d99abdf3c874f47195619a31ff5c12c7 (MD5) Made available in DSpace on 2015-11-17T12:18:41Z (GMT). No. of bitstreams: 1 RieszWolff_RIA.pdf: 159825 bytes, checksum: d99abdf3c874f47195619a31ff5c12c7 (MD5) Previous issue date: 2015-04

Pure mathematicsWolff potentialScale (ratio)Weak Lebesgue spaceVariable exponentMathematics::Classical Analysis and ODEsLebesgue's number lemmaNon-standard growth conditionIntegrability of solutionssymbols.namesakeMathematics - Analysis of PDEsReal interpolationFOS: MathematicsLp spaceMathematicsLaplace's equationMathematics::Functional AnalysisVariable exponentIntegrability estimatesRiesz potentialApplied MathematicsMathematical analysisFunctional Analysis (math.FA)Mathematics - Functional AnalysissymbolsRiesz potential47H99 (Primary) 46B70 46E30 35J60 31C45 (Secondary)Analysis of PDEs (math.AP)
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Multiple solutions of second order Hamiltonian systems

2017

Author(s): Bonanno, G; Livrea, R; Schechter, M | Abstract: The existence and the multiplicity of periodic solutions for a parameter dependent second order Hamiltonian system are established via linking theorems. A monotonicity trick is adopted in order to prove the existence of an open interval of parameters for which the problem under consideration admits at least two non trivial qualified solutions.

Pure mathematicscritical pointsMonotonic functionperiodic solutionsCritical points01 natural sciencesHamiltonian systemCritical pointsecond order Hamiltonian systemsQA1-939Order (group theory)0101 mathematicsMathematicsDiscrete mathematicsSecond order Hamiltonian systems; Periodic solutions; Critical points; Applied MathematicsPeriodic solutionsApplied Mathematics010102 general mathematicsMultiplicity (mathematics)Pure Mathematics010101 applied mathematicsSecond order Hamiltonian systemPeriodic solutionSecond order Hamiltonian systemsParameter dependentOpen intervalMathematics
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Infinitely many weak solutions for a mixed boundary value system with (p_1,…,p_m)-Laplacian

2014

The aim of this paper is to prove the existence of infinitely many weak solu- tions for a mixed boundary value system with (p1, . . . , pm)-Laplacian. The approach is based on variational methods.

Pure mathematicscritical pointsinfinitely many solutionsApplied MathematicsMathematical analysisvariational methodsBoundary valuesCritical points variational methods infinitely many solutions p-Laplacian.$p$-laplacianSettore MAT/05 - Analisi MatematicaQA1-939Laplace operatorMathematicsMathematics
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