v 2 1 4 Ja n 20 05 Ultrametric pseudodifferential operators and wavelets for the case of non homogeneous measure

We consider ultrametric space with a measure, such that the measure of any ball is positive. A family of orthonormal bases of ultrametric wavelets in the space of quadratically integrable functions is introduced. Pseudodifferential operators (PDO) in the ultrametric space are investigated. We prove that these operators are diagonal in the introduced bases of ultrametric wavelets and compute the corresponding eigenvalues. Duality between ultrametric spaces and directed trees is discussed. In particular, a new way of construction of ultrametric spaces by completion of directed trees is proposed.