# Automorphism groups over a hyperimaginary

@inproceedings{Kim2021AutomorphismGO, title={Automorphism groups over a hyperimaginary}, author={Byunghan Kim and Hyo-Tae Lee}, year={2021} }

In this paper we study the Lascar group over a hyperimaginary e. We verify that various results about the group over a real set still hold when the set is replaced by e. First of all, there is no written proof in the available literature that the group over e is a topological group. We present an expository style proof of the fact, which even simplifies existing proofs for the real case. We further extend a result that the orbit equivalence relation under a closed subgroup of the Lascar group… Expand

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