A note on a theorem by Aldo Ghizzetti

In this article, we explore some aspects of Fourier analysis on fuzzy sets. In particular, we give a complete characterization of the Fourier coefficients of fuzzy subsets of the unit circle. The main result hinges on a theorem by the Italian mathematician Aldo Ghizzetti. This work was part of a broader project jointly with Professor Vittorio Cafagna, who, sadly, passed away unexpectedly in 2007. His intellectual breadth and inspiring passion for mathematics still keeps shining today.