Parallel Feedback Turing Computability.

In contrast to most kinds of computability studied in mathematical logic, feedback computability has a non-degenerate notion of parallelism. Here we study parallelism for the most basic kind of feedback, namely that of Turing computability. We investigate several different possible definitions of parallelism in this context, with an eye toward specifying what is so computable. For the deterministic notions of parallelism identified we are successful in this analysis; for the non-deterministic notion, not completely.