We show that every language in PSPACE decidable by a Turing machine in time $T(n)=n^{O(\log n)}$ admits a doubly efficient interactive proof system: the prover runs in time polynomial in T(n), and the verifier runs in time polynomial in n. This extends the best previously known regime for such proof ... more >>>

For a quantified Boolean formula (QBF), the problem of computing the number of winning strategies is known as the #QBF problem. This problem is considered harder than the analogous #SAT problem. Recently, important proof systems for QBFs and #SAT have been studied. By extending the ideas from both fields, we ... more >>>

We show that the bipartite matching problem is in NC. We extend the result to weighted bipartite matching and the computation of the noncommutative rank of a symbolic matrix. In particular, this implies that the decision version of linear matroid intersection is in NC as well. The techniques are based ... more >>>