515 58j5358j5058j5165n2535p1511f7253c2034l1534e0557r18 abstract algebra analysisonmanifolds analyticfunctions asymptotictheory boundaryvalueproblems congresses differentialequations differentialgeometry differentialtopology diffraction discontinuousgroupsandautomorphicforms eigenvalueproblems eigenvalues electromagneticwaves estimationofeigenvalues extremalproblems(mathematics) feynmanintegrals globalanalysis globalanalysis(mathematics) globaldifferentialgeometry globalriemanniangeometry includingpinching initialvalueproblems integralequations isospectrality linear manifoldsandcellcomplexes mat002010 mathematicalanalysis mathematicalphysics mathematics numbertheory numericalanalysis numericalsolutions ordinarydifferentialequations ordinarydifferentialoperators orthogonalpolynomials partial partialdifferentialequations partialdifferentialequationsonmanifolds;differentialoperators perturbation(mathematics) perturbationmethods physics qa347 quantumcomputing quantumtheory queuingtheory randomwalks(mathematics) relationsbetweenspectraltheoryandergodictheory shapetheory(topology) spectralgeometry spectralproblems;spectralgeometry;scatteringtheory spectraltheory;selbergtraceformula spectraltheoryandeigenvalueproblems topologyandgeometryoforbifolds upperandlowerbounds waves