2025/01/21 by Candela, Pablo, González-Sánchez, Diego, Szegedy, Balázs · 1 citation
#Combinatorics (math.CO) #FOS: Mathematics #Spectral Theory (math.SP)
paper · doi:10.48550/arxiv.2501.12287
Our goal is to provide simple and practical algorithms in higher-order Fourier analysis which are based on spectral decompositions of operators. We propose a general framework for such algorithms and provide a detailed analysis of the quadratic case. Our results reveal new spectral aspects of the theory underlying higher-order Fourier analysis. Along these lines, we prove new inverse and regularity theorems for the Gowers norms based on higher-order character decompositions. Using these results, we prove a spectral inverse theorem and a spectral regularity theorem in quadratic Fourier analysis.