Minimal Indices
The set of minimal indices of a Goedelnumbering f is defined as
MIN = {e: (for all i < e)[f_i is different from f_e]}.
It has been known since 1972 that MIN is Turing equivalent to 0'',
but beyond this MIN has remained mostly uninvestigated. I will give an overview
of results known about MIN from the literature, and point out many open problems
along the way.
The material for this talk is taken from my paper
on minimal indices.