Capítulo de livro

Pseudo Differential operators of principal type

2009; Springer Nature; Linguagem: Inglês

10.1007/978-3-642-00136-9_3

ISSN

2512-5257

Autores

Lars Hörmander,

Tópico(s)

Advanced Mathematical Modeling in Engineering

Resumo

SummaryIn Section 10.4 we saw that the strength of a differential operator with constant coefficients in ℝ n is determined by the principal part p if and only if p=0 implies dp≠0 in ℝ n \0. Such operators were said to be of principal type. The purpose of this chapter is to study general operators P∈Ψ phg m (X) on a manifold X assuming that the condition dp ≠0 when p =0 is valid in a suitably strengthened form which makes the properties of p independent of lower order terms.

Referência(s)
Altmetric
PlumX