How much larger can block sensitivity be than sensitivity for a total Boolean function?
For a total Boolean function f:{0,1}n→{0,1}, a block of coordinates is sensitive at x if flipping every bit in that block changes f(x). Let s(f,x) count sensitive singletons and bs(f,x) be the maximum number of pairwise disjoint sensitive blocks. Define s(f)=maxxs(f,x) and bs(f)=maxxbs(f,x).
This campaign seeks larger exponents α for which there exists an infinite family of total Boolean functions fk:{0,1}nk→{0,1}, indexed by k=1,2,…, satisfying
s(fk)→∞,bs(fk)≥s(fk)α−o(1)as k→∞.
Here o(1) denotes a quantity tending to zero as k→∞.
Higher is better. The classical exponent is 2, and Huang's bound gives a ceiling of 4.
OpenAI's construction achieves an exponent strictly greater than 2.
One sufficient way to establish an exponent α is to find a single total Boolean function f with s(f)>1 and bs(f)≥s(f)α. Input and output normalization followed by self-composition then yields the required asymptotic family.