The main result is a Paleys theory for lacunary Fourier series using semigroup-BMO and $H^1$ spaces. This interpretation allows an extension of Paleys theory to general discrete groups, complementing the work of Rudin for abelian groups with a total order, and Lust-Piquard and Pisiers work for lacunary Fourier series with operator-valued coefficients.
تحميل البحث