"This research monograph integrates ideas from category theory, algebra and combinatorics. It is organized in three parts. Part I belongs to the realm of category theory. It reviews some of the foundational work of Bňabou, Eilenberg, Kelly and Mac Lane on monoidal categories and…
We study the higher Frobenius-Schur indicators of modules over semisimple Hopf algebras, and relate them to other invariants as the exponent, the order, and the index. We prove various divisibility and integrality results for these invariants. In particular, we prove a version o…
Is there a vector space whose dimension is the golden ratio? Of course not the golden ratio is not an integer! But this can happen for generalizations of vector spaces objects of a tensor category. The theory of tensor categories is a relatively new field of mathematics that gen…
