diff --git a/draft/draft.tex b/draft/draft.tex index 1e526a6..253e706 100644 --- a/draft/draft.tex +++ b/draft/draft.tex @@ -311,7 +311,7 @@ }% }% } -\newcommand{\sub}{\mathcal{S}} +\newcommand{\sub}{\mathcal{D}_{\leq1}} \newcommand{\bba}{ @@ -745,7 +745,8 @@ From now on, we use $\spa_a$ and $\rel_a$ to denote the categories of spans and \end{proof} % \begin{prop}\label{prop:rel-rela} - Assuming that $(X_1 \stackrel{p_1}{\leftarrow} R \stackrel{p_2}{\to}X_2)$ and $(Y_1 \stackrel{q_1}{\leftarrow} S \stackrel{q_2}{\to}Y_2)$, are objects of both categories $\rel$ and $\rel_a$, there is a morphism $(g_1,g_2)\c(X_1 \stackrel{p_1}{\leftarrow} R \stackrel{p_2}{\to}X_2)\to(Y_1 \stackrel{q_1}{\leftarrow} S \stackrel{q_2}{\to}Y_2)$ in $\rel_a$ iff there is a morphism $(g_1,g_2,w)$ of the same type in $\rel$, with the unique witness $w\c R\to S$. +Let $(X_1 \stackrel{p_1}{\leftarrow} R \stackrel{p_2}{\to}X_2)$ and $(Y_1 \stackrel{q_1}{\leftarrow} S \stackrel{q_2}{\to}Y_2)$ +be jointly-monic spans. Then there is a morphism $(g_1,g_2)\c(X_1 \stackrel{p_1}{\leftarrow} R \stackrel{p_2}{\to}X_2)\to(Y_1 \stackrel{q_1}{\leftarrow} S \stackrel{q_2}{\to}Y_2)$ in $\rel_a$ iff there is a morphism $(g_1,g_2,w)$ of the same type in $\rel$, with the unique witness $w\c R\to S$. \end{prop} \begin{proof} % $(\Rightarrow):$ We define $w$ as $w=\brks{g_1\comp p_1,g_2\comp p_2}$. We have: @@ -835,7 +836,7 @@ From now on, we use $\spa_a$ and $\rel_a$ to denote the categories of spans and \draw[-{Latex[length=2mm]}] (m-1-2) to[bend right=10] (m-2-2); % \end{tikzpicture} - \caption{Summery of results in this section about when we have a morphism in the source of an arrow then we have a morphism in the target in $\Set$.} + \caption{Summary of results in this section about when we have a morphism in the source of an arrow then we have a morphism in the target in $\Set$.} \label{fig:morph-summery} \end{figure} %\begin{notation} @@ -1642,7 +1643,7 @@ We have two more notions for coalgebraic bisimulation in $\Set$, that is to defi \draw[-{Latex[length=2mm]}] (m-3-1) to[bend right=5] (m-2-2); \end{tikzpicture} - \caption{Summery of results in this section about notions of simulation in $\Set$.} + \caption{Summary of results in this section about notions of simulation in $\Set$.} \label{fig:sim-summery} \end{figure} %\begin{center} @@ -1756,7 +1757,8 @@ Traditionally, simulations in $\Set$ are defined using relators. In this section They all follow in an obvious way from~\autoref{lem:liftable} and~\autoref{lem:coliftable}. The last one needs $\appr\comp\appr=\appr$ that comes from transitivity of $\appr$. \qed \end{proof} \begin{cor} - Assuming that the order structure $\appr$ on a functor $F\c\Set\to\Set$ is liftable and coliftable, all the notions of simulation given by relators mentioned in~\autoref{ex:lax-rels}. + Assuming that the order structure $\appr$ on a functor $F\c\Set\to\Set$ is liftable and coliftable, all the notions of simulation given by relators mentioned in~\autoref{ex:lax-rels} + are equivalent. \end{cor} % \begin{prop}\label{prop:HeJ-HuJ}