opposite 2-category

A 2-category $K$ has three different opposites (two independent):

- The
**$1$-cell dual**$K^{op}$, in which the $1$-cells but not the $2$-cells are reversed. - The
**$2$-cell dual**$K^{co}$, in which the $2$-cells but not the $1$-cells are reversed. - The
**bidual**$K^{co op}$ in which both $1$-cells and $2$-cells are reversed.

Revised on October 29, 2014 21:59:43
by Maciej Pirog?
(94.13.34.130)