Homogeneous and, more generally, quasihomogeneous distributions represent an important subclass of L. Schwartz's distributions. In this book, the meromorphic dependence of these distributions on the order of homogeneity and on further parameters is studied. The analytic continuation, the residues and the finite parts of these distribution-valued functions are investigated in some detail. This research was initiated by Marcel Riesz in his seminal article in Acta Mathematica in 1949. It leads to the so-called elliptic and hyperbolic M. Riesz kernels referring to the Laplace and the wave operator. The distributional formulation goes back to J. Dieudonne and J. Horvath. The analytic continuation of these distribution-valued functions yields convolution groups and fundamental solutions of the corresponding linear partial differential operators with constant coefficients. The convolvability and the convolution of distributions and, in particular, of quasihomogeneous distributions are investigated systematically. In contrast to most textbooks on distribution theory, the general concept of convolution of distributions is employed. It was defined by L. Schwartz and further analyzed by R. Shiraishi and J. Horvath. The authors Norbert Ortner (* 1945, Vorarlberg) and Peter Wagner (* 1956, Tirol) are well-known researchers in the fields of Distribution Theory and Partial Differential Equations. The latter is professor for mathematics at the Technical Faculty, the first one was professor for mathematics at the Faculty of Mathematics, Computer Science and Physics of the Innsbruck University.

This monograph provides the theoretical foundations needed for the construction of fundamental solutions and fundamental matrices of (systems of) linear partial differential equations. Many illustrative examples also show techniques for finding such solutions in terms of integrals. Particular attention is given to developing the fundamentals of distribution theory, accompanied by calculations of fundamental solutions. The main part of the book deals with existence theorems and uniqueness criteria, the method of parameter integration, the investigation of quasihyperbolic systems by means of Fourier and Laplace transforms, and the representation of fundamental solutions of homogeneous elliptic operators with the help of Abelian integrals. In addition to rigorous distributional derivations and verifications of fundamental solutions, the book also shows how to construct fundamental solutions (matrices) of many physically relevant operators (systems), in elasticity, thermoelasticity, hexagonal/cubic elastodynamics, for Maxwell's system and others. The book mainly addresses researchers and lecturers who work with partial differential equations. However, it also offers a valuable resource for students with a solid background in vector calculus, complex analysis and functional analysis.

This monograph provides the theoretical foundations needed for the construction of fundamental solutions and fundamental matrices of (systems of) linear partial differential equations. Many illustrative examples also show techniques for finding such solutions in terms of integrals. Particular attention is given to developing the fundamentals of distribution theory, accompanied by calculations of fundamental solutions. The main part of the book deals with existence theorems and uniqueness criteria, the method of parameter integration, the investigation of quasihyperbolic systems by means of Fourier and Laplace transforms, and the representation of fundamental solutions of homogeneous elliptic operators with the help of Abelian integrals. In addition to rigorous distributional derivations and verifications of fundamental solutions, the book also shows how to construct fundamental solutions (matrices) of many physically relevant operators (systems), in elasticity, thermoelasticity, hexagonal/cubic elastodynamics, for Maxwell's system and others. The book mainly addresses researchers and lecturers who work with partial differential equations. However, it also offers a valuable resource for students with a solid background in vector calculus, complex analysis and functional analysis.