Distributive Adjoint Strings

R. Rosebrugh and R. J. Wood

For an adjoint string V -| W -| X -| Y : B --> C, with Y fully faithful, it is frequently, but not always, the case that the composite VY underlies an idempotent monad. When it does, we call the string distributive. We also study shorter and longer `distributive' adjoint strings and how to generate them. These provide a new construction of the simplicial 2-category, Delta.

Keywords: adjoint functor, distributivity, simplicial 2­category.

AMS Classification (1991): 18A40, 18C15.

Theory and Applications of Categories, Vol. 1, 1995, No. 6, pp 119-145.


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