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Transactions of the American Mathematical Society
Transactions of the American Mathematical Society
ISSN 1088-6850(e) ISSN 0002-9947(p)

     

On the commensurator of the Nottingham group

Author(s): Mikhail Ershov
Journal: Trans. Amer. Math. Soc. 362 (2010), 6663-6678.
MSC (2010): Primary 20F28; Secondary 20E18, 20F40
Posted: August 3, 2010
MathSciNet review: 2678990
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Abstract | References | Similar articles | Additional information

Abstract: Let $ p\geq 5$ be a prime number. We prove that the abstract commensurator of the Nottingham group $ \mathcal{N}(\mathbb{F}_p)$ coincides with its automorphism group, which is known to be a finite extension of $ \mathcal{N}(\mathbb{F}_p)$. As a corollary we deduce that the Nottingham group cannot be embedded as an open subgroup of a topologically simple group.


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Additional Information:

Mikhail Ershov
Affiliation: Department of Mathematics, University of Virginia, Charlottesville, Virginia 22904
Email: ershov@virginia.edu

DOI: 10.1090/S0002-9947-2010-05160-8
PII: S 0002-9947(2010)05160-8
Received by editor(s): October 20, 2008
Received by editor(s) in revised form: May 4, 2009
Posted: August 3, 2010
Additional Notes: This material is based upon work supported by the National Science Foundation under agreement No. DMS-0111298. Any opinions, findings and conclusions or recommendations expressed in this material are those of the author and do not necessarily reflect the views of the National Science Foundation
Copyright of article: Copyright 2010, American Mathematical Society
The copyright for this article reverts to public domain after 28 years from publication.




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