Dr Cian O'Brien

PhD, BSc

Contact Details

Postdoctoral Researcher
E: ciansamuel.obrien@nuigalway.ie
http://www.maths.nuigalway.ie/~cobrien/
 
researcher
 

Biography

I am currently working as a postdoctoral researcher and lecturer in NUI Galway. Broadly, my research interests are generally in the areas of combinatorics of graphs and matrices, with a specific focus on structures relating to alternating sign matrices.

Research Interests

My main objects of study are alternating sign matrices, which are (0,1,-1)-matrices in which the non-zero entries of each row and column alternate in sign, beginning and ending with 1. Particular objects of interest to me include alternating signed bipartite graphs and related edge colouring problems, alternating sign hypermatrices and related Latin-like square structures, finite subgroups of GL(n,Q) generated by alternating sign matrices, and algebraic structures relating to alternating sign matrices when their entries are considered to be elements of F_3.

Peer Reviewed Journals

  Year Publication
(2020) 'Alternating sign hypermatrix decompositions of Latin-like squares'
C. O'Brien (2020) 'Alternating sign hypermatrix decompositions of Latin-like squares'. Advances in Applied Mathematics, 121 [DOI] [Details]
(2020) 'Alternating signed bipartite graphs and difference-1 colourings'
C. O'Brien, K. Jennings, R. Quinlan (2020) 'Alternating signed bipartite graphs and difference-1 colourings'. Linear Algebra And Its Applications, 604 :370-398 [DOI] [Details]

Teaching Interests

Group Theory, Linear Algebra, Discrete Mathematics, Algebraic Structures, Python Programming.

Modules Taught

  Term/Year Module Title Module Code Subject / Desc
2020 Programming for Science and Finance CS2101