2012/09/05 by Joachim von Below, Delio Mugnolo
Computer Science · Mathematics · #Advanced Mathematical Modeling in Engineering #Boundary value problem #Differential operator #Eigenvalues and eigenvectors #Hilbert space #Mathematical analysis #Mathematics #Matrix Theory and Algorithms #Operator (biology) #Pure mathematics #Self-adjoint operator #Spectral Theory in Mathematical Physics #Spectrum (functional analysis) #Vector space #math.AP #math.FA #math.SP #msc:05C50 #msc:34B45 #msc:34L10 #msc:34L20 #msc:35J25
paper · pdf · doi:10.1016/j.laa.2013.05.011
arxiv created 2012/09/05 · openalex publication_date 2013/06/14 · arxiv updated 2018/12/21 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
We consider a large class of self-adjoint elliptic problem associated with the second derivative acting on a space of vector-valued functions. We present two different approaches to the study of the associated eigenvalues problems. The first, more general one allows to replace a secular equation (which is well-known in some special cases) by an abstract rank condition. The latter seems to apply particularly well to a specific boundary condition, sometimes dubbed "anti-Kirchhoff" in the literature, that arise in the theory of differential operators on graphs; it also permits to discuss interesting and more direct connections between the spectrum of the differential operator and some graph theoretical quantities. In either case our results yield, among other, some results on the symmetry of the spectrum.