Willem Heijltjes: "Free sums and products: when zero times zero is not zero"
Datum objave: 18. 10. 2010
Seminar za temelje matematike in teoretično računalništvo
Torek, 19. 10. 2010, od 12h do 14h, Plemljev seminar, Jadranska 19
Willem Heijltjes
University of Edinburgh
Abstract: Products and coproducts in category theory are an abstract generalisation of the products and sums encountered in various guises across many fields of mathematics.
In this talk I consider those properties of sums and products that are common to all situations in which they occur. For example, it is not generally the case that sums distribute over products nor even that zero times zero is zero.
The main technical content is a graphical representation of "free" sums and products, i.e., ones in which no special properties are assumed. The graphical representation solves the word problem for free sums and products, using a simple rewriting procedure to canonical normal forms.
Vabljeni!
