9. Basics of hypercontractivity🔗

Reasonable random variables, Boolean hypercontractivity, low-degree norm and tail inequalities, small-set expansion, KKL applications, and Friedgut's Junta Theorem.

1. 9.1. Low-degree polynomials are reasonable
2. 9.2. Small subsets of the hypercube are noise-sensitive
3. 9.3. Single-bit hypercontractivity
4. 9.4. Two-function hypercontractivity and induction
5. 9.5. Applications of hypercontractivity
6. 9.6. The Kahn--Kalai--Linial Theorem
7. 9.7. Exercises and notes