Undecidable tiling problems in the hyperbolic plane
In his earlier paper [Invent. Math. 12, 177--209 (1970; Zbl 0197.46801)] the author proposed the problem of extending to the hyperbolic plane the undecidability and nonperiodicity results known for tilings of the Euclidean plane. In the present paper he succeeds in extending the undecidability results for the simplest case, that is, the origin-constrained case. He also finds a set of 49 polygons for which the completion problem is undecidable. The other problems remain open.
scientific article; zbMATH DE number 3551487