The fact that the Fourier characters $\chi_{\gamma} : {\mathbb F}_2^n \to \{-1,1\}$ form a group isomorphic to ${\mathbb F}_2^n$ is not a coincidence; the analogous result holds for any finite abelian group and is a special case of the theory of Pontryagin duality in harmonic analysis. We will see further examples of this in Chapter [...]

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Ohad Klein: In 26, in the "Affine subspace partition" definition, "may b...Ohad Klein: In the very end of prop 12, I think there should be an index...Ohad Klein: In 25 (also in the book) "one one child".Noam Lifshitz: In corollary 17, should it be $\widehat{\mathrm{Maj}_n}(S) =...Ohad Klein: In 49 (56 in the book), it looks like a typo: $E[f_i(y^(j))]...Ryan O'Donnell: Hope so; I'm quite happy with it so far. (Thanks to all who...Yi Zhang: I got it now!!