Peter Koepke
(University of Bonn)
Infinite Time Blum-Shub-Smale Machines

A notion of computability involving natural numbers can often be generalized to computability using ordinal numbers. We give a general overview of the field of ordinal computability and then concentrate on Infinite Time Blum-Shub-Smale Machines (ITBM). We show that the set of ITBM-computable reals coincides with the reals in the level Lωω of Gödel's constructible universe.