Department of
Math & CS

Joy Morris

BSc., Trent University
PhD, Simon Fraser University
Professor
 

Address: Joy Morris
Department of Mathematics & Computer Science
University of Lethbridge
4401 University Drive
Lethbridge, AB
CANADA     T1K 3M4
           
Phone: (403) 332-4100
Fax: (403) 317-2882
Office: C536
E-mail: joy.morris@uleth.ca

Teaching Activities     

Fall 2021
Math 3400, Section A
Math 3860, Section A


Spring 2022 - Summer 2022
(no teaching duties)

I've been interviewed in an ED Talk video talking about teaching.

Open Access Text Books
Proofs and Concepts
co-authored with Dave Morris. An undergraduate text book introducing proof techniques. We use this for a 2nd-year university course.
Combinatorics
An upper-level undergraduate text book for an introductory course in combinatorics, including enumeration, graph theory, and design theory. We use this for a 3rd-year university course.

Parent Math Help Drop-In
In 2017 I worked with Lethbridge School District 51 and PS 2 Math Education students at the University of Lethbridge to hold an 8-week drop-in program. This program was a help session for parents who were seeking help in understanding the math their children are learning, or who are looking for fun activities that will help their children learn to achieve middle school math outcomes (from the Alberta curriculum). We reached an estimated 100 individuals over the course of the program. A video about these sessions is available on YouTube, through this link. There have been subsequent sessions in 2018 (see this Global News video), 2019 (see this Lethbridge Herald article), and 2020.

Research Activities     

My research interests are in Combinatorics, in particular Algebraic Graph Theory (Cayley Graphs). I have published a number of papers. These include the papers available for download below in .pdf format. Many of the papers below represent joint work, as indicated in the authorship.

Connectivity of Cayley Graphs: A Special Family (Appeared in JCMCC, 1996)
Isomorphic Cayley Graphs on different Groups (Appeared in Congressus Numerantium, 1996)
Automorphism groups with Cyclic Commutator Subgroups and Hamilton Cycles (With E. Dobson, H. Gavlas and D. Witte. Appeared in Discrete Math., 1998)
Isomorphic Cayley Graphs on Nonisomorphic Groups (Appeared in JGT, 1999)
Self-complementary Circulant Graphs (With B. Alspach and V. Vilfred. Appeared in Ars Combinatoria, 1999)
Classifying Arc-Transitive Circulants of Squarefree Order (With C. H. Li and D. Marusic. Appeared in JACO, 2001)
Toida's Conjecture is True (With E. Dobson. Appeared in Electronic J. of Combin., 2002)
Results towards showing Z_p^n is a CI-group (Appeared in Congressus Numerantium, 2002)
Stitching Images Back Together (With F. Lutscher, J. McNulty, and K. Seyffarth. Appeared in Congressus Numerantium, 2003)
On automorphism groups of circulant digraphs of square-free order (With E. Dobson. Appeared in Discrete Math., 2005)
Flows that are sums of hamiltonian cycles in Cayley graphs on abelian groups (With D. Morris and D. Moulton. Appeared in Discrete Math., 2005)
Brian Alspach and his work (With M. Sajna. Appeared in Discrete Math., 2005)
Normal circulant graphs with noncyclic regular subgroups (With D. Marusic. Appeared in JGT, 2005)
Automorphism groups of circulant graphs - a survey (Appeared in Graph Theory, Trends in Math., Birkhauser, 2006)
Cyclic hamiltonian cycle systems of the complete graph minus a 1-factor (With H. Jordon. Appeared in Discrete Math., 2008)
Automorphism groups of wreath product digraphs (With E. Dobson. Appeared in Electronic J. of Combin., 2009)
Directed cyclic hamiltonian cycle systems of the complete symmetric digraph (With H. Jordon. Appeared in Discrete Math., 2009)
Hamiltonian cycles in (2,3,c)-circulant digraphs (With D. Morris and K. Webb. Appeared in Discrete Math., 2009)
Strongly regular edge-transitive graphs (With C. Praeger and P. Spiga. Appeared in Ars Mathematica Contemporanea, 2009)
Balanced Cayley graphs and balanced planar graphs (With P. Spiga and K. Webb. Appeared in Discrete Math., 2010)
Hamiltonian cycles in Cayley graphs whose order has few prime factors (With K. Kutnar, D. Marusic, D. Morris and P. Sparl. Appeared in Ars Mathematica Contemporanea, 2012.)
Cayley graphs of order 16p are hamiltonian (With S. Curran and D. Morris. Appeared in Ars Mathematica Contemporanea, 2012.)
Generalised quadrangles with a group of automorphisms acting primitively on points and lines (With J. Bamberg, M. Giudici, G. Royle and P. Spiga. Appeared in J. Combin. Theory - A, 2012.)
On the automorphism groups of almost all circulant graphs and digraphs (With S. Bhoumik and E. Dobson. Appeared in Ars Math. Comtemp., 2014.)
Automorphisms of Cayley graphs on generalised dicyclic groups, (With P. Spiga and G. Verret. Appeared in Europ. J. Combin., 2015.)
Affine transformations of finite vector spaces with large orders or few cycles, (With S. Guest, C. Praeger, and P. Spiga. Appeared in J. Pure and Applied Alg., 2015.)
Elementary proof that (Z_p)^4 is a DCI-group. (Appeared in Discrete Math., 2015.)
Quotients of CI-groups are CI-groups, (With E. Dobson. Appeared in Graphs and Combin., 2015.)
Semiregular automorphisms of cubic vertex-transitive graphs and the abelian normal quotient method, (With P. Spiga and G. Verret. Appeared in Electronic. J. Combin., 2015.)
On colour-preserving automorphisms of Cayley graphs, (With A. Hujdurovic, K. Kutnar, and D. Morris. Appeared in Ars. Math. Contemp., 2015.)
On the maximum orders of elements of finite almost simple groups and primitive permutation groups, (With S. Guest, C. Praeger, and P. Spiga. Appeared in Trans. Amer. Math. Soc., 2015.)
Further restrictions on the structure of finite DCI-groups: an addendum, (With E. Dobson and P. Spiga. Appeared in J. Alg. Combin., 2015.)
Λ-transitive digraphs preserving a cartesian decomposition (With P. Spiga. Appeared in J. of Australian Math. Sci., 2015.)
Finite primitive permutation groups containing a permutation having at most four cycles, (With S. Guest, C. Praeger, and P. Spiga. Appeared in J. Alg., 2016.)
Automorphisms of circulants that respect partitions, (Appeared in Contributions to Discrete Math., 2016.)
Isomorphisms of Cayley graphs on nilpotent groups, (With D. Morris and G. Verret. Appeared in New York J. Math., 2016.)
The CI problem for infinite groups, (Appeared in Electronic J. Combin., 2016.)
Vertex-transitive digraphs with extra automorphisms that preserve the natural arc-colouring, (With E. Dobson, A. Hujdurovic, and K. Kutnar. Appeared in Australasian J. Combin., 2017.)
Cyclic m-Cycle Systems of Complete Graphs minus a 1-factor, (With H. Jordon. Appeared in Australasian J. Combin., 2017.)
On Color Preserving Automorphisms of Cayley Graphs of Odd Square-free Order, (With E. Dobson, A. Hujdurovic, and K. Kutnar. Appeared in J. Alg. Combin., 2017)
Every finite non-solvable group admits an Oriented Regular Representation, (With P. Spiga. Appeared in by J. Combin. Theory - B, 2017.)
Characterising CCA Sylow cyclic groups whose order is not divisible by four, (With L. Morgan and G. Verret. Appeared in Ars. Math. Contemp., 2018)
Most Rigid Representations and Cayley Index, (With J. Tymburski. Appeared in Art of Disc. and App. Math., 2018)
Automorphism groups of circulant digraphs with applications to semigroup theory, (With J. Araujo, W. Bentz, E. Dobson, and J. Konieczny. Appeared in Combinatorica, 2018.)
Classification of finite groups that admit an oriented regular representation, (With P. Spiga. Appeared in Bull. London Math. Soc., 2018)
Digraphs with small automorphism groups that are Cayley on two nonisomorphic groups, (With L. Morgan and G. Verret. Appeared in Art of Disc. and App. Math., 2020)
A finite simple group is CCA if and only if it has no element of order four, (With L. Morgan and G. Verret. Appeared in J. Algebra, 2021)
Asymptotic enumeration of Cayley digraphs, (With P. Spiga. Accepted by Israel J. Math.)
Two new families of non-CCA groups, (With B. Fuller. Accepted by Art of Disc. and App. Math.)
Two families of graphs that are Cayley on nonisomorphic groups, (With J. Smolcic. Accepted by J. Alg., Comb., Disc. Structures, and Apps.)
Groups for which it is easy to detect graphical regular representations, (With D. Morris and G. Verret. Accepted by Art of Disc. and App. Math.)
Cayley graphs of more than one abelian group, (With E. Dobson. Accepted by Art of Disc. and App. Math.)
Classification of vertex-transitive digraphs via automorphism group, (With E. Dobson, A. Hujdurovic, and K. Kutnar. Submitted to Electronic J. Combin.)
On the asymptotic enumeration of Cayley graphs, (With M. Moscatiello and P. Spiga. Submitted to Ann. di Math. Pura e App.)
Most generalized Petersen graphs of girth 8 have cop number 4, (With T. Runte and A. Skelton. Submitted to Australasian J. Combin.)
On generalised Petersen graphs of girth 7 that have cop number 4, (With H. Morris. Submitted to Art of Disc. and App. Math.)

(Note: Dates inside the early files represent the dates on which I converted them to .pdf form, and may bear no relation to their publication dates. The files are not usually the final published version of the paper, due to copyright issues.)

Here are slides from the plenary talk I gave at the 8th Slovenian Conference on Graph Theory, June 2015. I have removed most of the page breaks from the slides.

I married Dave Morris in December of 2002. Here is a wedding photo.