d abstract) Nathan Segerlind∗ Sam Buss† Russell Impagliazzo‡ We prove a new switching lemma that works for restrictions that set only a small fraction of the variables and is applicable to DNFs with small conjunctions. We use this to prove lower bounds for the Res(k) propositional proof system, an extension of resolution which works with k-DNFs instead of clauses. We also obtain an exponential separation between depth d circuits of bottom fan-in k and depth d circuits of bottom fan-in
Nathan Segerlind, Samuel R. Buss, Russell Impaglia