منابع مشابه
Isomorphism of hierarchical structures
0. Int roduction Th is paper concerns certain hierarchical tilings of Euclidean space, of which a well known example is a ‘kite and dart’ tiling of the plane [Gar ]. Such tilings are noted for two properties: their unusual rotational symmetries (‘ten-fold symmetry’), and the fact that their global structures derive from local (‘matching’) rules. We will examine th e consequences of different ch...
متن کاملIsomorphism of Hierarchical
We consider hierarchical structures such as Fibonacci sequences and Penrose tilings, and examine the consequences of diierent choices for the deenition of isomorphism. In particular we discuss the role such a choice plays with regard to matching rules for such structures.
متن کاملIsomorphism of Homogeneous Structures
We consider the complexity of the isomorphism relation on countable first-order structures with transitive automorphism groups. We use the theory of Borel reducibility of equivalence relations to show that the isomorphism problem for vertex-transitive graphs is as complicated as the isomorphism problem for arbitrary graphs, and determine for which first-order languages the isomorphism problem f...
متن کاملIsomorphism relations on computable structures
We study the complexity of the isomorphism relation on classes of computable structures. We use the notion of FF -reducibility introduced in [9] to show completeness of the isomorphism relation on many familiar classes in the context of all Σ1 equivalence relations on hyperarithmetical subsets of ω.
متن کاملOn Isomorphism Invariants of Some Automatic Structures
In this paper we study structures defined by finite automata, called automatic structures. We provide a method that reduces the study of automatic structures to the study of automatic graphs. We investigate isomorphism invariants of automatic structures with an emphasis to equivalence relation structures, linearly ordered sets, and permutation structures.
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: Ergodic Theory and Dynamical Systems
سال: 2001
ISSN: 0143-3857,1469-4417
DOI: 10.1017/s0143385701001572