On the theory of differential boundary problems
On the theory of differential boundary problems
复制标题
微分边界问题理论
DOI:
--
复制
发表时间:
1963
期刊:
影响因子:
--
通讯作者:
M. Schechter
中科院分区:
文献类型:
--
作者:
M. Schechter
In a previous publication [10] the author applied the method of negative norms to elliptic boundary value problems. It was shown how inequalities involving such norms led to solutions of boundary problems for distributions. Existence theorems were easily obtained together with powerful regularity results. In this paper we extract the essential features of the method and apply them to general boundary problems for arbitrary partial differential equations. The problems are posed in such a way as to include ,all types of equations and boundary conditions. We seek necessary and sufficient conditions for the existence of classical, strong, and weak solutions. These conditions are usually expressed by means of inequalities (a priori estimates). In applying the theory one would have to show that a certain inequality is satisfied. Existence then follows automatically. In some particular cases (e.g., the Viik-Sobolev problems, cf. 5) it was discovered that the required inequalities were already known, giving the desired existence theorems immediately. Our main tools are representation theorems for bounded linear functionals on the spaces Ht’(G) and their subspaces, where is an arbitrary integer, p an arbitrary real number greater than one, and G an arbitrary domain in Euclidean n-space (cf. Theorems 2.1, 2.2, 6.2, 6.3, 7.1). For => 0, Ht’’(G) is defined as the completion of C(C1 G) with respect to the norm