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Fundamental results for pseudo-differetial operators of type 1,1
This paper develops some deeper consequences of an extended definition,
proposed previously by the author, of pseudo-differential operators that are of
type in H\"ormander's sense. Thus, it contributes to the long-standing
problem of creating a systematic theory of such operators. It is shown that
type -operators are defined and continuous on the full space of temperate
distributions, if they fulfil H\"ormander's twisted diagonal condition, or more
generally if they belong to the self-adjoint subclass; and that they are always
defined on the temperate smooth functions. As a main tool the paradifferential
decomposition is derived for type -operators, and to confirm a natural
hypothesis the symmetric term is shown to cause the domain restrictions;
whereas the other terms are shown to define nice type -operators
fulfilling the twisted diagonal condition. The decomposition is analysed in the
type -context by combining the Spectral Support Rule and the factorisation
inequality, which gives pointwise estimates of pseudo-differential operators in
terms of maximal functions.Comment: 40 pages. Contents identical to version published on 16 May 2016 by
Axioms (only the styles differ
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