text/appendixes/comparing_defs.tex
changeset 432 35755232f6ad
parent 417 d3b05641e7ca
parent 431 2191215dae10
child 433 c4c1a01a9009
equal deleted inserted replaced
418:a96f3d2ef852 432:35755232f6ad
   198 \nn{to be continued...}
   198 \nn{to be continued...}
   199 \medskip
   199 \medskip
   200 
   200 
   201 \subsection{$A_\infty$ $1$-categories}
   201 \subsection{$A_\infty$ $1$-categories}
   202 \label{sec:comparing-A-infty}
   202 \label{sec:comparing-A-infty}
   203 In this section, we make contact between the usual definition of an $A_\infty$ algebra 
   203 In this section, we make contact between the usual definition of an $A_\infty$ category 
   204 and our definition of a topological $A_\infty$ algebra, from Definition \ref{defn:topological-Ainfty-category}.
   204 and our definition of a topological $A_\infty$ $1$-category, from \S \ref{???}.
   205 
   205 
   206 We begin be restricting the data of a topological $A_\infty$ algebra to the standard interval $[0,1]$, 
   206 That definition associates a chain complex to every interval, and we begin by giving an alternative definition that is entirely in terms of the chain complex associated to the standard interval $[0,1]$. 
   207 which we can alternatively characterise as:
       
   208 \begin{defn}
   207 \begin{defn}
   209 A \emph{topological $A_\infty$ category on $[0,1]$} $\cC$ has a set of objects $\Obj(\cC)$, 
   208 A \emph{topological $A_\infty$ category on $[0,1]$} $\cC$ has a set of objects $\Obj(\cC)$, 
   210 and for each $a,b \in \Obj(\cC)$, a chain complex $\cC_{a,b}$, along with
   209 and for each $a,b \in \Obj(\cC)$, a chain complex $\cC_{a,b}$, along with
   211 \begin{itemize}
   210 \begin{itemize}
   212 \item an action of the operad of $\Obj(\cC)$-labeled cell decompositions
   211 \item an action of the operad of $\Obj(\cC)$-labeled cell decompositions
   220 them to form a new cell decomposition $\cJ^{(1)} \circ_m \cJ^{(2)}$ by inserting the points 
   219 them to form a new cell decomposition $\cJ^{(1)} \circ_m \cJ^{(2)}$ by inserting the points 
   221 of $\cJ^{(2)}$ linearly into the $m$-th interval of $\cJ^{(1)}$.
   220 of $\cJ^{(2)}$ linearly into the $m$-th interval of $\cJ^{(1)}$.
   222 In the $X$-labeled case, we insist that the appropriate labels match up.
   221 In the $X$-labeled case, we insist that the appropriate labels match up.
   223 Saying we have an action of this operad means that for each labeled cell decomposition 
   222 Saying we have an action of this operad means that for each labeled cell decomposition 
   224 $0 < x_1< \cdots < x_k < 1$, $a_0, \ldots, a_{k+1} \subset \Obj(\cC)$, there is a chain 
   223 $0 < x_1< \cdots < x_k < 1$, $a_0, \ldots, a_{k+1} \subset \Obj(\cC)$, there is a chain 
   225 map $$\cC_{a_0,a_1} \tensor \cdots \tensor \cC_{a_k,a_{k+1}} \to \cC(a_0,a_{k+1})$$ and these 
   224 map $$\cC_{a_0,a_1} \tensor \cdots \tensor \cC_{a_k,a_{k+1}} \to \cC_{a_0,a_{k+1}}$$ and these 
   226 chain maps compose exactly as the cell decompositions.
   225 chain maps compose exactly as the cell decompositions.
   227 An action of $\CD{[0,1]}$ is compatible with an action of the cell decomposition operad 
   226 An action of $\CD{[0,1]}$ is compatible with an action of the cell decomposition operad 
   228 if given a decomposition $\pi$, and a family of diffeomorphisms $f \in \CD{[0,1]}$ which 
   227 if given a decomposition $\pi$, and a family of diffeomorphisms $f \in \CD{[0,1]}$ which 
   229 is supported on the subintervals determined by $\pi$, then the two possible operations 
   228 is supported on the subintervals determined by $\pi$, then the two possible operations 
   230 (glue intervals together, then apply the diffeomorphisms, or apply the diffeormorphisms 
   229 (glue intervals together, then apply the diffeomorphisms, or apply the diffeormorphisms