Natural geometric Fourier transforms and the associated fractional Laplacian

To each arbitrary given general geometric structure on ${\mathbb{R}}^n$, we associate a pair of compatible Fourier transforms, that prove to appear naturally in the framework of Poisson’s summation formula for full lattices. We study their properties and the compatibility with the classical $n-$dimensional Fourier transform. In the case of a positive definite geometric structure, we show that these geometric Fourier transforms induce a geometric fractional Laplacian, with properties similar to those of the classical fractional Laplacian.