# Wadge hardness in Scott spaces and its effectivization

@article{Becher2014WadgeHI, title={Wadge hardness in Scott spaces and its effectivization}, author={Ver{\'o}nica Becher and Serge Grigorieff}, journal={Mathematical Structures in Computer Science}, year={2014}, volume={25}, pages={1520 - 1545} }

We prove some results on the Wadge order on the space of sets of natural numbers endowed with Scott topology, and more generally, on omega-continuous domains. Using alternating decreasing chains we characterize the property of Wadge hardness for the classes of the Hausdorff difference hierarchy (iterated differences of open sets). A similar characterization holds for Wadge one-to-one and finite-to-one completeness. We consider the same questions for the effectivization of the Wadge relation. We…

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