We prove that for all $\varepsilon>0$, there exists a positive integer $k$ such that given a $4$-to-$1$ Game $\Psi$ with alphabet size at most $k$, it is NP-hard to distinguish between the case that val$(\Psi)=1$ and the case that val$(\Psi)\leq \delta$. This confirms the $4$-to-$1$ Games Conjecture from [Khot, CCC ... more >>>

We use this framework to construct HSGs for read-once CNFs and read-once CNFs with parities. For formulas on $n$ variables with density at least $\varepsilon$, our generators use $O(\log(n/\varepsilon))$ seed bits. This bound is optimal up to a constant factor. Applying the hitting reduction of Gopalan, Meka, Reingold, Trevisan, and ... more >>>

The Group Epimorphism Problem (GpEpi) asks, given two finite groups $G_1$ and $G_2$, whether there exists a surjective group homomorphism, or epimorphism, from $G_1$ to $G_2$. When the input groups are given by their multiplication (Cayley) tables, the problem admits a quasipolynomial-time algorithm in general, but little is known about ... more >>>