Laplace versus Fourier II (La venganza)

Encontré esto aquí, cito sin traducir:

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The FT exists for any finite energy signal, and a scalar product what is
usually called by engineers the cross-corrleation, can be defined and
proved that the cross-correlation is the same in time as in frequency
domain (Parseval's theorem). This gives a Hilbert (vector) space
structure for the FT. There is no such resuslt for LT (not even if it
is two-sided LT) and one could argue that that is the reason why FT is
so interesting.

For FT they are all defined on the same lines, time and frequency. The
difficulty with LT is that the LT of different functions have
different regions of holomorphy and that, so-to-speak, has to be
"sorted" out. 

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Ya no estoy tan seguro que sea un punto para los ingenieros... :-(