Regular abelian coverings of cyclic hypermaps
Maureemootoo, Dawn Irene (2000) Regular abelian coverings of cyclic hypermaps. University of Southampton, Department of Mathematics, Doctoral Thesis , 165pp.
Download
PDF
Restricted to System admin Download (22Mb) 
Description/Abstract
The foundations of this work lie in the use of representation theory
to find lattices of regular hypermaps H arising as elementary abelian
coverings of some regular hypermap Ji such that Aut(Tt) = CR. It is
assumed that Aut(7f) = C™ X CR a spUt extension of an elementary
abelian group with cyclic complement. Examples of this situation are
found in [2] where regular orientable imbeddings of the complete graph
Kq, q = pe with p a prime integer, were classified and enumerated. Initial
investigations are of maps obtained from regular orientable imbeddings
of certain highly symmetrical subgraphs Kq of Kq. Results pertaining
to the number and valency of vertices, edges, faces, Petrie polygons, the
genus, the automorphism group and reflexibility are found to be similar
to those obtained in [2]. Subsequently, a description is given of the
general construction. Determination of the lattice of coverings H of H
is found to be dependent upon the signature of the mapsubgroup T of
H. Results are obtained for the cases where Tab is a torsion group and
where F"6 is a free abelian group. Hypermap operations induced by outer
automorphisms of the triangle group A(R, R, oo) are also considered
here. The hypermaps are regular of type (R, R,p) and, once again, have
automorphism group C™ XI CR. It was found that when n = 1 these
hypermaps lie in a single orbit under the group of hypermap operations,
whilst when n = 2 they have orbit length <p{R)2 in case R\p  1 and
length (p(R)2/2 otherwise.
Item Type:  Thesis (Doctoral)  

Subjects:  Q Science > QA Mathematics  
Divisions:  University Structure  Pre August 2011 > School of Mathematics 

ePrint ID:  50625  
Date : 


Date Deposited:  19 Mar 2008  
Last Modified:  27 Mar 2014 18:33  
URI:  http://eprints.soton.ac.uk/id/eprint/50625 
Actions (login required)
View Item 
Downloads from ePrints over the past year. Other digital versions may also be available to download e.g. from the publisher's website.