The Beurling and Malliavin theorem in several dimensions
摘要
The present paper is devoted to a new multidimensional generalization of the First Beurling and Malliavin Theorem, which is a classical result in the Uncertainty Principle in Fourier Analysis. In more detail, we establish a new sufficient condition for a radial function to be a Beurling and Malliavin majorant in several dimensions (this means that the function in question can be minorized by the modulus of a square integrable function which is not zero identically and which has the support of the Fourier transform included in an arbitrary small ball). As a corollary of the radial case, we also obtain a new sharp sufficient condition in the nonradial case. The latter result provides a partial answer to the question posed by L. Hörmander in the paper [