Date of Award
6-1-2015
Document Type
Dissertation
Degree Name
Ph.D.
Organizational Unit
College of Natual Science and Mathematics
First Advisor
Petr Vojtěchovský, Ph.D.
Second Advisor
Scott Leutenegger
Third Advisor
Nikolaos Galatos
Fourth Advisor
Michael Kinyon
Fifth Advisor
Andrew Linshaw
Sixth Advisor
Izabella Stuhl
Keywords
Automorphic loops, Dihedral-like automorphic loops, Cauchy and Lagrange theorems for groups
Abstract
In this dissertation we study dihedral-like constructions of automorphic loops. Automorphic loops are loops in which all inner mappings are automorphisms. We start by describing a generalization of the dihedral construction for groups. Namely, if (G , +) is an abelian group, m > 1 and α ∈2 Aut(G ), let Dih(m, G, α) on Zm × G be defined by
(i, u )(j, v ) = (i + j , ((-1)j u + v )αij ).
We prove that the resulting loop is automorphic if and only if m = 2 or (α2 = 1 and m is even) or (m is odd, α = 1 and exp(G ) ≤ 2). In the last case, the loop is a group. The case m = 2 was introduced by Kinyon, Kunen, Phillips, and Vojtěchovský.
We study basic structural properties of dihedral-like automorphic loops. We describe certain subloops, including: nucleus, commutant, center, associator subloop and derived subloop. We prove theorems for dihedral-like automorphic loops analogous to the Cauchy and Lagrange theorems for groups, and further we discuss the coset decomposition in dihedral-like automorphic loops.
We show that two finite dihedral-like automorphic loops Dih( m, G, α) and Dih(m̅, Ḡ, ᾱ) are isomorphic if and only if m= m̅, G [congruent with] Ḡ and α is conjugate to ᾱ in Aut(G ). We describe the automorphism group of Q and its subgroup consisting of inner mappings of Q .
Finally, due to the solution to the isomorphism problem, we are interested in studying conjugacy classes of automorphism groups of finite abelian groups. Then we describe all dihedral-like automorphic loops of order < 128 up to isomorphism. We conclude with a description of all dihedral-like automorphic loops of order < 64 up to isotopism.
Publication Statement
Copyright is held by the author. User is responsible for all copyright compliance.
Rights Holder
Mouna Ramadan Aboras
Provenance
Received from ProQuest
File Format
application/pdf
Language
en
File Size
101 p.
Recommended Citation
Aboras, Mouna Ramadan, "Dihedral-Like Constructions of Automorphic Loops" (2015). Electronic Theses and Dissertations. 3.
https://digitalcommons.du.edu/etd/3
Copyright date
2015
Discipline
Mathematics