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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Ryan O'Donnell: Thanks!Ryan O'Donnell: Yeah, Chapter 13 doesn't exist. :( On the bright side, the ...Kirill Elagin: “In Chapter 13 we will show” =(Kirill Elagin: Typo (examples 22, bullet 2): “task is to fund”.Ryan O'Donnell: Argh! I specifically remember double-checking your name. G...Gautam Kamath: Thanks, I will wear this title with pride! As another (in...Ryan O'Donnell: Thanks Mom! For you, a free copy :)