Locally coalgebra-Galois extensions
نویسنده
چکیده
The paper introduces the notion of a locally coalgebra-Galois extension and, as its special case, a locally cleft extension, generalising concepts from [9]. The necessary and sufficient conditions for a locally coalgebra-Galois extension to be a (global) coalgebra-Galois extension are stated. As an important special case, it is proven, that under not very restrictive conditions the gluing of two locally cleft extensions is a globally coalgebra-Galois extension. As an example, the quantum lens space of positive charge is constructed by gluing of two quantum solid tori.
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