Portland State University. Department of Mathematics and Statistics
Date of Award
Doctor of Philosophy (Ph.D.) in Mathematical Sciences
Mathematics and Statistics
1 online resource (vii, 91 pages)
Boolean algebra, Permutation groups
An orthomorphism, π, of a group, (G, +), is a permutation of G with the property that the map x → -x + π(x) is also a permutation. In this paper, we consider orthomorphisms of the additive group of binary n-tuples, Zn2. We use known orthomorphism preserving functions to prove a uniformity in the cycle types of orthomorphisms that extend certain partial orthomorphisms, and prove that extensions of particular sizes of partial orthomorphisms exist. Further, in studying the action of conjugating orthomorphisms by automorphisms, we find several symmetries within the orbits and stabilizers of this action, and other orthomorphism-preserving functions. In addition, we prove a lower bound on the number of orthomorphisms of Zn2 using the equivalence of orthomorphisms to transversals in Latin squares. Lastly, we present a Monte Carlo method for generating orthomorphisms and discuss the results of the implementation.
Schimanski, Nichole Louise, "Orthomorphisms of Boolean Groups" (2016). Dissertations and Theses. Paper 3100.