In linear algebra there are two equivalent definitions of what it means for a function to be linear:

Definition 29 A function $f : {\mathbb F}_2^n \to {\mathbb F}_2$ is linear if either of the following equivalent conditions hold:

$f(x+y) = f(x) + f(y)$ for all $x, y \in {\mathbb [...]

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Matt Franklin: Maybe two small typos in last sentence before Borell's Isope...Matt Franklin: maybe small typo in Remark 11.11 (p. 328 in book): $z \tild...Matt Franklin: Maybe small typo in 2nd line of analysis of "second factor o...Matt Franklin: maybe small typo in 2nd line of establishing (10.24) on p. 3...Ryan O'Donnell: Right, thanks!Ryan O'Donnell: They should, though someone else reported this bug already :...Ryan O'Donnell: I agree it's not extremely clear. I'll see if I can rework ...