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**Pseudo-differential operators and the Nash-Moser theorem.
(Opérateurs pseudo-différentiels et théorème de Nash-Moser.)**
*(French)*
Zbl 0791.47044

Savoirs Actuels. Paris: InterEditions. Paris: Editions du CNRS. 188 p. (1991).

As the authors state in the introduction, this is an elementary presentation of the theorem of Nash-Moser, and related topics. The organization of this book is as follows. Chapter 0 gathers the basics on the theory of distributions. On Chapter 1 the authors present a theory of classical pseudo-differential operators, with emphasis on symbolic calculus. Chapter 2 is dedicated to Littlewood-Paley theory, microlocal analysis, and energy estimates. Finally, Chapter 3 is divided in three sections, covering implicit function theorems, the use of fixed point theorems, and Nash-Moser theorem. Every chapter closes with a commentary and a list of problems.

Although the book is aimed at students, or newcomers to the subject, the careful and knowledgeable presentation makes its reading a treat for anybody interested in the interplay of ideas coming from the theory of PDE, Harmonic analysis and Operator theory.

The problems presented at the end of each chapter are a special and welcome feature. They are for the most part nontrivial and in occasions down right difficult. The latter are marked \(^*\) and altogether, they make for a great and unusual addition to a book of this nature. The authors should be congratulated for putting the time and effort required to compile such a good problem selection.

The book closes with a list of notations and a short bibliography classified as prerequisites, readings at a comparable level, and advanced reading.

Although the book is aimed at students, or newcomers to the subject, the careful and knowledgeable presentation makes its reading a treat for anybody interested in the interplay of ideas coming from the theory of PDE, Harmonic analysis and Operator theory.

The problems presented at the end of each chapter are a special and welcome feature. They are for the most part nontrivial and in occasions down right difficult. The latter are marked \(^*\) and altogether, they make for a great and unusual addition to a book of this nature. The authors should be congratulated for putting the time and effort required to compile such a good problem selection.

The book closes with a list of notations and a short bibliography classified as prerequisites, readings at a comparable level, and advanced reading.

Reviewer: J.Alvarez (Las Cruces)

### MSC:

47G30 | Pseudodifferential operators |

35S05 | Pseudodifferential operators as generalizations of partial differential operators |

42B25 | Maximal functions, Littlewood-Paley theory |

46F10 | Operations with distributions and generalized functions |

46F05 | Topological linear spaces of test functions, distributions and ultradistributions |

46-01 | Introductory exposition (textbooks, tutorial papers, etc.) pertaining to functional analysis |