Agarwal, Ravi P.; O’Regan, Donal Nonlinear boundary value problems on time scales. (English) Zbl 0995.34016 Nonlinear Anal., Theory Methods Appl., Ser. A, Theory Methods 44, No. 4, 527-535 (2001). This paper contains several results on the existence of one or two nonnegative solutions to the nonlinear second-order dynamic equation on a measure chain (time scale) \({\mathbf T}\), i.e., \[ y^{\Delta\Delta}(t)+f(t,y(\sigma(t)))=0, \quad t\in[a,b]\cap {\mathbf T}, \] subject to the boundary conditions \[ y(a)=0, \quad y^\Delta(\sigma(b))=0. \] The theory of dynamic equations on measure chains unifies and extends the differential (\({\mathbf T}={\mathbb{R}}\)) and difference (\({\mathbf T}={\mathbb{Z}}\)) equations theories. The results extend the ones by L. Erbe and A. Peterson [Math. Comput. Modelling 32, No. 5-6, 571—585 (2000; Zbl 0963.34020)], and are also closely related to results by C. J. Chyan, J. Henderson and H. C. Lo [Tamkang J. Math. 30, No. 3, 231-240 (1999; Zbl 0995.34017)]. The proofs are based on an application of a nonlinear alternative of Leray-Schauder-type or Krasnoselskii fixed-point theorems. The paper will be useful for researchers interested in nonnegative solutions to differential or difference equations, and/or in dynamic equations on measure chains (time scales). Reviewer: Roman Hilscher (East Lansing) Cited in 1 ReviewCited in 86 Documents MSC: 34B18 Positive solutions to nonlinear boundary value problems for ordinary differential equations 34B45 Boundary value problems on graphs and networks for ordinary differential equations 39A99 Difference equations Keywords:measure chain (time scale); dynamic equation; nonnegative solution; fixed-point theorem Citations:Zbl 0963.34020; Zbl 0995.34017 PDF BibTeX XML Cite \textit{R. P. Agarwal} and \textit{D. O'Regan}, Nonlinear Anal., Theory Methods Appl., Ser. A, Theory Methods 44, No. 4, 527--535 (2001; Zbl 0995.34016) Full Text: DOI References: [1] Agarwal, R. P.; Bohner, M., Basic calculus on time scales and some of its applications, Results Math., 35, 3-22 (1999) · Zbl 0927.39003 [4] Erbe, L. H.; Peterson, A., Green’s functions and comparison theorems for differential equations on measure chains, Dynamics Continuous, Discrete Impulsive Systems, 6, 121-138 (1999) [6] Hilgar, S., Analysis on measure chains – a unified approach to continuous and discrete calculus, Results Math., 18, 18-56 (1990) This reference list is based on information provided by the publisher or from digital mathematics libraries. Its items are heuristically matched to zbMATH identifiers and may contain data conversion errors. It attempts to reflect the references listed in the original paper as accurately as possible without claiming the completeness or perfect precision of the matching.