##
**Inverse source problems.**
*(English)*
Zbl 0721.31002

Mathematical Surveys and Monographs, 34. Providence, RI: American Mathematical Society (AMS). xiv, 193 p. (1990).

The book is a review of the results on the inverse problem of potential theory (Chapters 2-5) supplemented by a discussion of some inverse problems for parabolic and hyperbolic equations (Chapters 6, 7). In Chapter 1 some auxiliary material is given. In Chapter 2 the results are described. In Chapter 3 uniqueness theorems are given. They are based on the idea of P. Novikov (1938). In Chapter 4 singularities of the exterior potentials are studied: relations between smoothness of the continuation of the potential across \(\Gamma\) and smoothness of \(\Gamma\), provided that the source and the coefficients of the operator are smooth. Some results of V. K. Ivanov are given. Chapter 5 deals with the existence of the mass distribution which generates a given harmonic function as an exterior potential. This is largely an open problem. Local existence results are described. An example of nonexistence is given. Chapters 6 and 7 deal with some inverse problems of parabolic and hyperbolic equations. Typically the extra data are given on the lateral surface of the cylinder or on its upper base.

[A detailed comment of the reviewer concerning omissions of other work and inaccuracies in the text of this book may be obtained from the editor on special request.]

[A detailed comment of the reviewer concerning omissions of other work and inaccuracies in the text of this book may be obtained from the editor on special request.]

Reviewer: A.G.Ramm (Manhatten)

### MSC:

31B20 | Boundary value and inverse problems for harmonic functions in higher dimensions |

35R30 | Inverse problems for PDEs |

31-02 | Research exposition (monographs, survey articles) pertaining to potential theory |

31B05 | Harmonic, subharmonic, superharmonic functions in higher dimensions |

35Kxx | Parabolic equations and parabolic systems |

35Lxx | Hyperbolic equations and hyperbolic systems |

35-02 | Research exposition (monographs, survey articles) pertaining to partial differential equations |