Search results for "superlinear reaction"

showing 8 items of 8 documents

Nonlinear nonhomogeneous Neumann eigenvalue problems

2015

We consider a nonlinear parametric Neumann problem driven by a nonhomogeneous differential operator with a reaction which is $(p-1)$-superlinear near $\pm\infty$ and exhibits concave terms near zero. We show that for all small values of the parameter, the problem has at least five solutions, four of constant sign and the fifth nodal. We also show the existence of extremal constant sign solutions.

Applied MathematicsConcave termnodal solutionMathematical analysisZero (complex analysis)superlinear reactionDifferential operatorExtremal constant sign solutionNonlinear systemMaximum principlemaximum principleNeumann boundary conditionextremal constant sign solutionsQA1-939superlinear reaction concave terms maximum principle extremal constant sign solutions nodal solution critical groupsconcave termsConstant (mathematics)critical groupsEigenvalues and eigenvectorsCritical groupMathematicsMathematicsSign (mathematics)Electronic Journal of Qualitative Theory of Differential Equations
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Solutions for parametric double phase Robin problems

2021

We consider a parametric double phase problem with Robin boundary condition. We prove two existence theorems. In the first the reaction is ( p − 1 )-superlinear and the solutions produced are asymptotically big as λ → 0 + . In the second the conditions on the reaction are essentially local at zero and the solutions produced are asymptotically small as λ → 0 + .

General Mathematics010102 general mathematicsasymptotically small solutionssuperlinear reactionC-conditionasymptotically big solutions01 natural sciences010101 applied mathematicsDouble phaseSettore MAT/05 - Analisi MatematicaUnbalanced growthApplied mathematics0101 mathematicsMathematicsParametric statisticsAsymptotic Analysis
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Parameter dependence for the positive solutions of nonlinear, nonhomogeneous Robin problems

2020

We consider a parametric nonlinear Robin problem driven by a nonlinear nonhomogeneous differential operator plus an indefinite potential. The reaction term is $$(p-1)$$-superlinear but need not satisfy the usual Ambrosetti–Rabinowitz condition. We look for positive solutions and prove a bifurcation-type result for the set of positive solutions as the parameter $$\lambda >0$$ varies. Also we prove the existence of a minimal positive solution $$u_\lambda ^*$$ and determine the monotonicity and continuity properties of the map $$\lambda \rightarrow u_\lambda ^*$$.

Pure mathematicsAlgebra and Number TheoryApplied MathematicsMathematics::Analysis of PDEsMonotonic functionNonlinearDifferential operatorLambdaBifurcation-type resultTerm (time)Positive solutionSet (abstract data type)Computational MathematicsNonlinear systemSettore MAT/05 - Analisi MatematicaIndefinite potentialNonhomogeneous differential operatorGeometry and TopologySuperlinear reaction termAnalysisNonlinear regularity theoryParametric statisticsMathematicsRevista de la Real Academia de Ciencias Exactas, Físicas y Naturales. Serie A. Matemáticas
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Solutions and positive solutions for superlinear Robin problems

2019

We consider nonlinear, nonhomogeneous Robin problems with a (p − 1)-superlinear reaction term, which need not satisfy the Ambrosetti-Rabinowitz condition. We look for positive solutions and prove existence and multiplicity theorems. For the particular case of the p-Laplacian, we prove existence results under a different geometry near the origin.We consider nonlinear, nonhomogeneous Robin problems with a (p − 1)-superlinear reaction term, which need not satisfy the Ambrosetti-Rabinowitz condition. We look for positive solutions and prove existence and multiplicity theorems. For the particular case of the p-Laplacian, we prove existence results under a different geometry near the origin.

Pure mathematicsnonlinear maximum principle010102 general mathematicsMathematics::Analysis of PDEssuperlinear reactionStatistical and Nonlinear PhysicsMultiplicity (mathematics)01 natural sciencesTerm (time)Nonlinear systempositive solutionSettore MAT/05 - Analisi Matematica0103 physical sciencesNonhomogeneous differential operatornonlinear regularity010307 mathematical physics0101 mathematicscritical groupsMathematical PhysicsMathematicsJournal of Mathematical Physics
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A multiplicity theorem for parametric superlinear (p,q)-equations

2020

We consider a parametric nonlinear Robin problem driven by the sum of a \(p\)-Laplacian and of a \(q\)-Laplacian (\((p,q)\)-equation). The reaction term is \((p-1)\)-superlinear but need not satisfy the Ambrosetti-Rabinowitz condition. Using variational tools, together with truncation and comparison techniques and critical groups, we show that for all small values of the parameter, the problem has at least five nontrivial smooth solutions, all with sign information.

Pure mathematicsnonlinear maximum principlelcsh:T57-57.97General MathematicsMathematics::Analysis of PDEssuperlinear reactionMultiplicity (mathematics)extremal solutionsSettore MAT/05 - Analisi Matematicalcsh:Applied mathematics. Quantitative methodsConstant sign and nodal solutionExtremal solutionnonlinear regularityconstant sign and nodal solutionscritical groupsCritical groupMathematicsParametric statisticsOpuscula Mathematica
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Superlinear Robin Problems with Indefinite Linear Part

2018

We consider a semilinear Robin problem with an indefinite linear part and a superlinear reaction term, which does not satisfy the usual in such cases AR condition. Using variational methods, together with truncation–perturbation techniques and Morse theory (critical groups), we establish the existence of three nontrivial solutions. Our result extends in different ways the multiplicity theorem of Wang.

Regularity theoryPure mathematicsGeneral Mathematics010102 general mathematicsThree solutions theoremMultiplicity (mathematics)Robin boundary condition01 natural sciencesRobin boundary conditionTerm (time)Indefinite potential function010101 applied mathematicsSettore MAT/05 - Analisi Matematica0101 mathematicsSuperlinear reaction termCritical groupMathematicsMorse theory
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Multiple solutions for semilinear Robin problems with superlinear reaction and no symmetries

2021

We study a semilinear Robin problem driven by the Laplacian with a parametric superlinear reaction. Using variational tools from the critical point theory with truncation and comparison techniques, critical groups and flow invariance arguments, we show the existence of seven nontrivial smooth solutions, all with sign information and ordered.

critical groupSettore MAT/05 - Analisi Matematicacritical point theoryConstant sign and nodal solutionsuperlinear reactionflow invariance
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Positive solutions for nonlinear Robin problems

2017

We consider a parametric Robin problem driven by the p-Laplacian with an indefinite potential and with a superlinear reaction term which does not satisfy the Ambrosetti-Rabinowitz condition. We look for positive solutions. We prove a bifurcation-type theorem describing the nonexistence, existence and multiplicity of positive solutions as the parameter varies. We also show the existence of a minimal positive solution $\tilde{u}_\lambda$ and establish the monotonicity and continuity of the map $\lambda\to \tilde{u}_\lambda$.

truncation and comparison techniquesminimax positive solutionSettore MAT/05 - Analisi Matematicalcsh:MathematicsMathematics::Analysis of PDEssuperlinear reactionRobin boundary condition superlinear reaction truncation and comparison techniques bifurcation-type result minimax positive solutionRobin boundary conditionbifurcation-type resultlcsh:QA1-939
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