École Nationale Polytechnique d'Oran, B.P. 1523 El M'naouar Oran 31000, Algeria
Аннотация:
In this paper, we show that the four-dimensional Lorentzian Damek–Ricci spaces are not a Ricci soliton. This is a generalization of the result of Tan and Deng (see 11) who proved that these spaces are not a Ricci soliton only with respect to the left-invariant vector fields.
Ключевые слова и фразы:Damek–Ricci spaces, Ricci soliton, left-invariant metrics, Lorentzian metrics.