Computability Learning Seminar

Jonny Stephenson, Department of Pure Mathematics, University of Waterloo

"Co-spectra"

The co-spectrum of a structure is the family of sets coded by the structure. This is a measure of how well we can encode information in the structure. We will see that every countable ideal in the e-degrees is the co-spectrum of a structure, and give a generalization of Richter's result on c.e.-minimal pairs.

MC 5403