General Harmonic analysis Analyse harmonique Boundary value problems Differential equations, Partial Équations aux dérivées partielles Functional analysis Geometry Harmonic analysis on Euclidean spaces Laplace-Operator MATHEMATICS Partial differential equations Problèmes aux limites Randwertproblem Riemannian manifolds Riemannscher Raum Variétés de Riemann Abstract Harmonic Analysis Algebraic Geometry Algebraic geometry Analysis Asymptotic distribution of eigenvalues and eigenfunctions Difference and functional equations Differential Equations Differential equations Existence, uniqueness, and regularity theory [See also 35Q30] Fluid mechanics {For general continuum mechanics, see 74Axx, or other parts of 74-XX} Fourier Analysis Fourier analysis Function spaces arising in harmonic analysis