Ma. Pinsky et Me. Taylor, POINTWISE FOURIER INVERSION - A WAVE-EQUATION APPROACH, The journal of fourier analysis and applications, 3(6), 1997, pp. 647-703
Functions of the Laplace operator F(-Delta) can be synthesized from th
e solution operator to the wave equation. When F is the characteristic
function of [0, R-2], this gives a representation for radial Fourier
inversion. A number of topics related to pointwise convergence or dive
rgence of such inversion, as R --> infinity, are studied in this artic
le. In some cases, including analysis on Euclidean space, spheres, hyp
erbolic space, and certain other symmetric spaces, exact formulas for
fundamental solutions to wave equations are available. In other cases,
parametrices and other tools of microlocal analysis are effective.