Downward Collapse from a Weaker Hypothesis

Edith Hemaspaandra, Lane A. Hemaspaandra, Harald Hempel

Hemaspaandra et al. proved that, for $m>0$ and $0<i<k-1$: if $Σ_i^p \BoldfaceDelta DIFF_m(Σ_k^p)$ is closed under complementation, then $DIF{F}_m({\Sigma }_k^p)=coDIF{F}_m({\Sigma }_k^p)$. T…