Seminario / Martins Ferreira
Lunedì 18 settembre 2017, alle ore 15.00, in Aula Dottorato,
il Prof. Nelson Martins Ferreira, Instituto Politécnico de Leiria,
terra' un seminario dal titolo:
"Trigraphs and its applications"
A trigraph is a straightforward generalization of a digraph (directed graph). If C is a category, then a digraph internal to C is a pair of parallel morphisms in C. Similarly, a trigraph internal to C is a triple of parallel morphisms in C. Two examples of trigraphs will be presented and characterized, namely the trigraphs that are constructed from a triangulated surface, and those that are originated from the multiplicative structure of an internal category or groupoid . In addition, we combine these results with a relative version with respect to a class of split epimorphisms in the sense of .
 N. Martins-Ferreira, "Triangulations, triangulated surfaces and the multiplicative structure of internal groupoids", (talk at the) International Conference on Category Theory (CT2017), University of British Columbia, Vancouver, Canada (16to22Jul2017)
 N. Martins-Ferreira, Internal precategories relative to split epimorphisms (2009) (arXiv:0903.0333)
This research work was supported by the Portuguese Foundation for Science and Technology (FCT) through the Project reference UID/ Multi/04044/2013,
and also by CDRSP and ESTG from the Polytechnic Institute of Leiria.