We present quasi-diagonal preconditioners for piecewise polynomial discretizations of pseudodifferential operators of order minus two in any space dimension. Here, quasi-diagonal means diagonal up to a sparse transformation. ...

The central role played by pseudodifferential operators in relativistic dynamics is known very well. In this work, operators like the Schrodinger one (e.g., square root) are treated from the point of view of the non-local ...

We investigate the Schrodinger representations of certain infinite-dimensional Heisenberg groups, using their corresponding Wigner transforms.

We define and study coherent states, a Berezin-Toeplitz quantization and covariant symbols on the product Xi := G x g(#) between a connected simply connected nilpotent Lie group and the dual of its Lie algebra. The starting ...

For families of magnetic pseudodifferential operators defined by symbols and magnetic fields depending continuously on a real parameter epsilon, we show that the corresponding family of spectra also varies continuously ...

In recent papers and books, a global quantization has been developed for unimodular groups of type I. It involves operator-valued symbols defined on the product between the group G and its unitary dual G^ , composed of ...

Abstract. This dissertation is dedicated to study two problems: the first one is the study of Riesz Kernels attached to elliptic quadratic forms of dimensions 4 and 2, and its applications to the construction of fundamental ...

We study bounded operators defined in terms of the regular representations of the C*-algebra of an amenable, Hausdorff, second countable, locally compact groupoid endowed with a continuous 2-cocycle. We concentrate on ...

The gauge covariant magnetic Weyl calculus has been introduced and studied in previous works. We prove criteria in terms of commutators for operators to be magnetic pseudodifferential operators of suitable symbol classes. ...