Search results for "Nonlinear"

showing 10 items of 3684 documents

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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A note on homoclinic solutions of (p,q)-Laplacian difference equations

2019

We prove the existence of at least two positive homoclinic solutions for a discrete boundary value problem of equations driven by the (p,q) -Laplace operator. The properties of the nonlinearity ensure that the energy functional, corresponding to the problem, satisfies a mountain pass geometry and a Palais–Smale compactness condition.

Pure mathematicsAlgebra and Number TheoryDifference equationApplied MathematicsOperator (physics)010102 general mathematicshomoclinic solution01 natural sciences010101 applied mathematicsNonlinear system(pq)-Laplace operatorpositive solutionSettore MAT/05 - Analisi MatematicaBoundary value problemHomoclinic orbitPalais–Smale condition0101 mathematicsLaplace operatorAnalysisMathematicsJournal of Difference Equations and Applications
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Some coincidence and periodic points results in a metric space endowed with a graph and applications

2015

The purpose of this paper is to obtain some coincidence and periodic points results for generalized $F$-type contractions in a metric space endowed with a graph. Some examples are given to illustrate the new theory. Then, we apply our results to establishing the existence of solution for a certain type of nonlinear integral equation.

Pure mathematicsAlgebra and Number TheoryPeriodic sequencePeriodic pointCoincidence point nonlinear integral equation periodic point.Type (model theory)TopologyNonlinear integral equationnonlinear integral equationCoincidenceCoincidence pointMetric spaceperiodic point54H25Settore MAT/05 - Analisi MatematicaGraph (abstract data type)05C40Coincidence pointAnalysis47H10Mathematics
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Multiplicity of solutions to a nonlinear boundary value problem of concave–convex type

2015

Abstract Problem (P) { − Δ p u + | u | p − 2 u = | u | r − 1 u x ∈ Ω | ∇ u | p − 2 ∂ u ∂ ν = λ | u | s − 1 u x ∈ ∂ Ω , where Ω ⊂ R N is a bounded smooth domain, ν is the unit outward normal at ∂ Ω , Δ p is the p -Laplacian operator and λ > 0 is a parameter, was studied in Sabina de Lis (2011) and Sabina de Lis and Segura de Leon (in press). Among other features, it was shown there that when exponents lie in the regime 1 s p r , a minimal positive solution exists if 0 λ ≤ Λ , for a certain finite Λ , while no positive solutions exist in the complementary range λ > Λ . Furthermore, in the radially symmetric case a second positive solution exists for λ varying in the same full range ( 0 , Λ ) …

Pure mathematicsApplied MathematicsBounded functionMathematical analysisRegular polygonMultiplicity (mathematics)Abstract problemNonlinear boundary value problemSymmetric caseLaplace operatorAnalysisMathematicsNonlinear Analysis: Theory, Methods & Applications
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Relations between natural and observable measures

2005

We give a complete description of relations between observable and natural measures in connection with invariance, ergodicity and absolute continuity.

Pure mathematicsApplied MathematicsErgodicityMathematical analysisGeneral Physics and AstronomyNatural (music)Statistical and Nonlinear PhysicsObservableAbsolute continuityDynamical system (definition)Mathematical PhysicsMathematicsConnection (mathematics)Nonlinearity
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Local multifractal analysis in metric spaces

2013

We study the local dimensions and local multifractal properties of measures on doubling metric spaces. Our aim is twofold. On one hand, we show that there are plenty of multifractal type measures in all metric spaces which satisfy only mild regularity conditions. On the other hand, we consider a local spectrum that can be used to gain finer information on the local behaviour of measures than its global counterpart.

Pure mathematicsApplied MathematicsGeneral Physics and AstronomyMetric Geometry (math.MG)Statistical and Nonlinear PhysicsDynamical Systems (math.DS)Multifractal systemType (model theory)28A80 28D20 54E50Metric spaceLocal spectrumMathematics - Metric GeometryMathematics - Classical Analysis and ODEsClassical Analysis and ODEs (math.CA)FOS: MathematicsMathematics - Dynamical SystemsMathematical PhysicsMathematicsNonlinearity
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Existence and gap-bifurcation of multiple solutions to certain nonlinear eigenvalue problems

1993

IN THIS PAPER we study: (i) a class of operator equations in an abstract Hilbert space; and (ii) the L2-theory of certain nonlinear Schrodinger equations which can be viewed as special cases of (i). In order to describe the type of abstract nonlinear eigenvalue problems to be discussed, consider a real Hilbert space H with scalar product (* , *) and norm II.11 and let S be a (not necessarily bounded) positive self-adjoint linear operator in li. We write S in the form

Pure mathematicsApplied MathematicsMathematical analysisHilbert spaceNonlinear systemsymbols.namesakeBounded functionNorm (mathematics)symbolsSpectral gapDivide-and-conquer eigenvalue algorithmAnalysisSelf-adjoint operatorEigenvalues and eigenvectorsMathematicsNonlinear Analysis: Theory, Methods & Applications
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Fixed point methods and accretivity for perturbed nonlinear equations in Banach spaces

2020

Abstract In this paper we use fixed point theorems to guarantee the existence of solutions for inclusions of the form A u + λ u + F u ∋ g , where A is a quasi-m-accretive operator defined in a Banach space, λ > 0 , and the nonlinear perturbation F satisfies some suitable conditions. We apply the obtained results, among other things, to guarantee the existence of solutions of boundary value problems of the type − Δ ρ ( u ( x ) ) + λ u ( x ) + F u ( x ) = g ( x ) , x ∈ Ω , and ρ ( u ) = 0 on ∂Ω, where the Laplace operator Δ should be understood in the sense of distributions over Ω and to study the existence and uniqueness of solution for a nonlinear integro-differential equation posed in L 1 …

Pure mathematicsApplied MathematicsOperator (physics)010102 general mathematicsBanach spaceFixed-point theoremFixed point01 natural sciences010101 applied mathematicsNonlinear systemBoundary value problemUniqueness0101 mathematicsLaplace operatorAnalysisMathematicsJournal of Mathematical Analysis and Applications
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Nonlinear vector Duffing inclusions with no growth restriction on the orientor field

2019

We consider nonlinear multivalued Dirichlet Duffing systems. We do not impose any growth condition on the multivalued perturbation. Using tools from the theory of nonlinear operators of monotone type, we prove existence theorems for the convex and the nonconvex problems. Also we show the existence of extremal trajectories and show that such solutions are $C_0^1(T,\mathbb{R}^N)$-dense in the solution set of the convex problem (strong relaxation theorem).

Pure mathematicsApplied MathematicsRegular polygonSolution setPerturbation (astronomy)Dirichlet distributionDuffing systemNonlinear systemsymbols.namesakeMonotone polygonNonlinear operator of mono-tone typeGrowth restrictionSettore MAT/05 - Analisi MatematicaConvex optimizationStrong relaxationssymbolsExtremal solutionAnalysisMathematics
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Weak solution for Neumann (p,q)-Laplacian problem on Riemannian manifold

2019

We prove the existence of a nontrivial solution for a nonlinear (p, q)-Laplacian problem with Neumann boundary condition, on a non compact Riemannian manifold. The idea is to reduce the problem in variational form, which means to consider the critical points of the corresponding Euler-Lagrange functional in an Orlicz-Sobolev space. (C) 2019 Elsevier Inc. All rights reserved.

Pure mathematicsApplied MathematicsWeak solution010102 general mathematicsRiemannian manifoldSpace (mathematics)01 natural sciences010101 applied mathematicsNonlinear systemSettore MAT/05 - Analisi MatematicaNeumann boundary condition(p q)-Laplacian operator Riemannian manifold Weak solution0101 mathematicsLaplace operatorAnalysisMathematics
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