nLab relaxed multicategory

Relaxed multicategories

Relaxed multicategories


Vertex algebras are intuitively analogues of associative algebras, except that certain singularities come up (in physics terminology this comes from OPE‘s).

Relaxed multicategories can be thought of, according to Borcherds, as multicategories in which the morphisms may have some sort of singularity. In the language of pseudotensor categories (a variant of coloured operads) this is studied by Beilinson and Drinfeld. In connection to quantum groups this has been studied by Soibelman.

Sketch of a definition

Let TT be the free monoid monad on Set and T +T^+ the monad induced by the adjunction of the forgetful functor from TT-multicategories to TT-graphs. Leinster defines a particular T +T^+-multicategory (see generalized multicategory) VV. A relaxed multicategory is any VV-enriched TT-multicategory.


Last revised on July 3, 2023 at 01:54:49. See the history of this page for a list of all contributions to it.