text/ncat.tex
changeset 812 14d12dff8268
parent 811 858b80dfa05c
child 816 233afb8cdae2
equal deleted inserted replaced
811:858b80dfa05c 812:14d12dff8268
  2616 with the roles of $\cC$ and $\cD$ reversed.
  2616 with the roles of $\cC$ and $\cD$ reversed.
  2617 These 2-morphisms come for free, in the sense of not requiring additional data, since we can take them to be the labeled 
  2617 These 2-morphisms come for free, in the sense of not requiring additional data, since we can take them to be the labeled 
  2618 cell complexes (cups and caps) in $B^2$ shown in Figure \ref{morita-fig-1}.
  2618 cell complexes (cups and caps) in $B^2$ shown in Figure \ref{morita-fig-1}.
  2619 \begin{figure}[t]
  2619 \begin{figure}[t]
  2620 $$\mathfig{.65}{tempkw/morita1}$$
  2620 $$\mathfig{.65}{tempkw/morita1}$$
       
  2621 
       
  2622 
       
  2623 $$
       
  2624 \begin{tikzpicture}
       
  2625 \node(L) at (0,0) {\tikz{
       
  2626 	\draw[orange] (0,0) -- node[below] {$\cC$} (1,0);
       
  2627 	\draw[blue] (1,0) -- node[below] {$\cD$} (2,0);
       
  2628 	\draw[orange] (2,0) -- node[below] {$\cC$} (3,0);
       
  2629 	\node[purple, fill, circle, inner sep=2pt, label=$\cM$] at (1,0) {};
       
  2630 	\node[purple, fill, circle, inner sep=2pt, label=$\cM$] at (2,0) {};
       
  2631 }};
       
  2632 
       
  2633 \node(R) at (6,0) {\tikz{
       
  2634 	\draw[orange] (0,0) -- node[below] {$\cC$} (3,0);
       
  2635 	\node[label={\phantom{$\cM$}}] at (1.5,0) {};
       
  2636 }};
       
  2637 
       
  2638 \node at (-1,-1.5) { $\leftidx{_\cC}{(\cM \tensor_\cD \cM)}{_\cC}$ };
       
  2639 \node at (7,-1.5) { $\leftidx{_\cC}{\cC}{_\cC}$ };
       
  2640 
       
  2641 \draw[->] (L) to[out=35, in=145] node[below] {$w$} node[above] { \tikz{
       
  2642 	\draw (0,0) circle (16pt);
       
  2643 }}(R);
       
  2644 
       
  2645 \draw[->] (R) to[out=-145, in=-35] node[above] {$x$} node[below] { \tikz{
       
  2646 	\draw (0,0) circle (16pt);
       
  2647 }}(L);
       
  2648 
       
  2649 
       
  2650 \end{tikzpicture}
       
  2651 $$
       
  2652 
  2621 \caption{Cups and caps for free}\label{morita-fig-1}
  2653 \caption{Cups and caps for free}\label{morita-fig-1}
  2622 \end{figure}
  2654 \end{figure}
  2623 
  2655 
  2624 
  2656 
  2625 We want the 2-morphisms from the previous paragraph to be equivalences, so we need 3-morphisms
  2657 We want the 2-morphisms from the previous paragraph to be equivalences, so we need 3-morphisms