nLab
opposite poset

Given a poset (or proset) PP, its opposite (or dual, inverse, converse, reverse, etc), denoted P opP^{op} (among other ways), is the poset (or proset) with the same underlying set, with xyx \leq y in P opP^op iff yxy \leq x (equivalently, xyx \geq y) in the original PP. This is a special case of both an opposite relation and an opposite category.

Last revised on August 27, 2018 at 18:38:23. See the history of this page for a list of all contributions to it.