text/ncat.tex
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    95 Morphisms are modeled on balls, so their boundaries are modeled on spheres.
    95 Morphisms are modeled on balls, so their boundaries are modeled on spheres.
    96 In other words, we need to extend the functors $\cC_{k-1}$ from balls to spheres, for 
    96 In other words, we need to extend the functors $\cC_{k-1}$ from balls to spheres, for 
    97 $1\le k \le n$.
    97 $1\le k \le n$.
    98 At first it might seem that we need another axiom for this, but in fact once we have
    98 At first it might seem that we need another axiom for this, but in fact once we have
    99 all the axioms in this subsection for $0$ through $k-1$ we can use a colimit
    99 all the axioms in this subsection for $0$ through $k-1$ we can use a colimit
   100 construction, as described in Subsection \ref{ss:ncat-coend} below, to extend $\cC_{k-1}$
   100 construction, as described in \S\ref{ss:ncat-coend} below, to extend $\cC_{k-1}$
   101 to spheres (and any other manifolds):
   101 to spheres (and any other manifolds):
   102 
   102 
   103 \begin{lem}
   103 \begin{lem}
   104 \label{lem:spheres}
   104 \label{lem:spheres}
   105 For each $1 \le k \le n$, we have a functor $\cl{\cC}_{k-1}$ from 
   105 For each $1 \le k \le n$, we have a functor $\cl{\cC}_{k-1}$ from 
   744 More generally, start with an $n{+}m$-category $C$ and a closed $m$-manifold $F$.
   744 More generally, start with an $n{+}m$-category $C$ and a closed $m$-manifold $F$.
   745 Define $\cC(X)$, for $\dim(X) < n$,
   745 Define $\cC(X)$, for $\dim(X) < n$,
   746 to be the set of all $C$-labeled embedded cell complexes of $X\times F$.
   746 to be the set of all $C$-labeled embedded cell complexes of $X\times F$.
   747 Define $\cC(X; c)$, for $X$ an $n$-ball,
   747 Define $\cC(X; c)$, for $X$ an $n$-ball,
   748 to be the dual Hilbert space $A(X\times F; c)$.
   748 to be the dual Hilbert space $A(X\times F; c)$.
   749 (See Subsection \ref{sec:constructing-a-tqft}.)
   749 (See \S\ref{sec:constructing-a-tqft}.)
   750 \end{example}
   750 \end{example}
   751 
   751 
   752 \noop{
   752 \noop{
   753 \nn{shouldn't this go elsewhere?  we haven't yet discussed constructing a system of fields from
   753 \nn{shouldn't this go elsewhere?  we haven't yet discussed constructing a system of fields from
   754 an n-cat}
   754 an n-cat}
  1506 
  1506 
  1507 \subsection{Morphisms of $A_\infty$ $1$-category modules}
  1507 \subsection{Morphisms of $A_\infty$ $1$-category modules}
  1508 \label{ss:module-morphisms}
  1508 \label{ss:module-morphisms}
  1509 
  1509 
  1510 In order to state and prove our version of the higher dimensional Deligne conjecture
  1510 In order to state and prove our version of the higher dimensional Deligne conjecture
  1511 (Section \ref{sec:deligne}),
  1511 (\S\ref{sec:deligne}),
  1512 we need to define morphisms of $A_\infty$ $1$-category modules and establish
  1512 we need to define morphisms of $A_\infty$ $1$-category modules and establish
  1513 some of their elementary properties.
  1513 some of their elementary properties.
  1514 
  1514 
  1515 To motivate the definitions which follow, consider algebras $A$ and $B$, 
  1515 To motivate the definitions which follow, consider algebras $A$ and $B$, 
  1516 right modules $X_B$ and $Z_A$ and a bimodule $\leftidx{_B}{Y}{_A}$, and the familiar adjunction
  1516 right modules $X_B$ and $Z_A$ and a bimodule $\leftidx{_B}{Y}{_A}$, and the familiar adjunction
  1875 
  1875 
  1876 More generally, consider an interval with interior marked points, and with the complements
  1876 More generally, consider an interval with interior marked points, and with the complements
  1877 of these points labeled by $n$-categories $\cA_i$ ($0\le i\le l$) and the marked points labeled
  1877 of these points labeled by $n$-categories $\cA_i$ ($0\le i\le l$) and the marked points labeled
  1878 by $\cA_i$-$\cA_{i+1}$ bimodules $\cM_i$.
  1878 by $\cA_i$-$\cA_{i+1}$ bimodules $\cM_i$.
  1879 (See Figure \ref{feb21c}.)
  1879 (See Figure \ref{feb21c}.)
  1880 To this data we can apply the coend construction as in Subsection \ref{moddecss} above
  1880 To this data we can apply the coend construction as in \S\ref{moddecss} above
  1881 to obtain an $\cA_0$-$\cA_l$ $0$-sphere module and, forgetfully, an $n{-}1$-category.
  1881 to obtain an $\cA_0$-$\cA_l$ $0$-sphere module and, forgetfully, an $n{-}1$-category.
  1882 This amounts to a definition of taking tensor products of $0$-sphere module over $n$-categories.
  1882 This amounts to a definition of taking tensor products of $0$-sphere module over $n$-categories.
  1883 
  1883 
  1884 \begin{figure}[!ht]
  1884 \begin{figure}[!ht]
  1885 $$
  1885 $$