On the commensurator of the Nottingham group

Author:
Mikhail Ershov

Journal:
Trans. Amer. Math. Soc. **362** (2010), 6663-6678

MSC (2010):
Primary 20F28; Secondary 20E18, 20F40

Published electronically:
August 3, 2010

MathSciNet review:
2678990

Full-text PDF Free Access

Abstract | References | Similar Articles | Additional Information

Abstract: Let be a prime number. We prove that the abstract commensurator of the Nottingham group coincides with its automorphism group, which is known to be a finite extension of . 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:
http://dx.doi.org/10.1090/S0002-9947-2010-05160-8

Received by editor(s):
October 20, 2008

Received by editor(s) in revised form:
May 4, 2009

Published electronically:
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

Article copyright:
© Copyright 2010
American Mathematical Society

The copyright for this article reverts to public domain 28 years after publication.