Integer Group of Coinvariants
نویسنده
چکیده
The local structure of a tiling is described in terms of a multiplicative structure on its pattern classes. The groupoid associated to the tiling is derived from this structure and its integer group of coinvariants is defined. This group furnishes part of the K0-group of the groupoid C ∗-algebra for tilings which reduce to decorations of Z Z . The group itself as well as the image of its state is computed for substitution tilings in case the substitution is locally invertible and primitive. This yields in particular the set of possible gap labels predicted by K-theory for Schrödinger operators describing the particle motion in such a tiling.
منابع مشابه
Integer Groups of Coinvariants Associated to Octagonal Tilings
The integer groups of coinvariants associated to undecorated and decorated octagonal tilings are computed.
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