From focussed proof systems to complexity bounds

  title={From focussed proof systems to complexity bounds},
  author={Anupam Das},
We conduct a complexity-theoretic study of focussed proof systems, relating the alternation of synchronous and asynchronous phases in a proof to an appropriate alternating time hierarchy, for instance the polynomial hierarchy. We propose a notion of ‘over-focussing’ that admits non-branching invertible rules during synchronous phases, due to the fact that deterministic computations can equally be carried out by a nondeterministic machine. As an application, we develop an over-focussed system… CONTINUE READING