Inverse Probleme für die Wärmeleitungsgleichung. (Inverse problems for the heat conductivity equation) (Q1118769)

The paper provides a summary of the results obtained in recent years for the unique determination of heat conductivity in the heat equation. The cases of a constant, space-dependent, time-dependent heat conductivity and the quasilinear case, i.e. the heat conductivity is a function of the temperature, are considered under some additional information on the temperature and on the heat flow, respectively. Moreover, a simple proof for the validity of the maximum principle in the quasilinear case is given.