text/ncat.tex
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  1134 Corresponding to this decomposition we have an action and/or composition map
  1134 Corresponding to this decomposition we have an action and/or composition map
  1135 from the product of these various sets into $\cM(X)$.
  1135 from the product of these various sets into $\cM(X)$.
  1136 
  1136 
  1137 \medskip
  1137 \medskip
  1138 
  1138 
  1139 
  1139 Part of the structure of an $n$-cat 0-sphere module is captured my saying it is
  1140 
  1140 a collection $\cD^{ab}$ of $n{-}1$-categories, indexed by pairs $(a, b)$ of objects (0-morphisms)
       
  1141 of $\cA$ and $\cB$.
       
  1142 Let $J$ be some standard 0-marked 1-ball (i.e.\ an interval with a marked point in its interior).
       
  1143 Given a $j$-ball $X$, $0\le j\le n-1$, we define
       
  1144 \[
       
  1145 	\cD(X) \deq \cM(X\times J) .
       
  1146 \]
       
  1147 The product is pinched over the boundary of $J$.
       
  1148 $\cD$ breaks into ``blocks" according to the restrictions to the pinched points of $X\times J$
       
  1149 (see Figure xxxx).
       
  1150 These restrictions are 0-morphisms $(a, b)$ of $\cA$ and $\cB$.
       
  1151 
       
  1152 More generally, consider an interval with interior marked points, and with the complements
       
  1153 of these points labeled by $n$-categories $\cA_i$ ($0\le i\le l$) and the marked points labeled
       
  1154 by $\cA_i$-$\cA_{i+1}$ bimodules $\cM_i$.
       
  1155 (See Figure xxxx.)
       
  1156 To this data we can apply to coend construction as in Subsection \ref{moddecss} above
       
  1157 to obtain an $\cA_0$-$\cA_l$ bimodule and, forgetfully, an $n{-}1$-category.
       
  1158 This amounts to a definition of taking tensor products of bimodules over $n$-categories.
       
  1159 
       
  1160 We could also similarly mark and label a circle, obtaining an $n{-}1$-category
       
  1161 associated to the marked and labeled circle.
       
  1162 (See Figure xxxx.)
       
  1163 If the circle is divided into two intervals, we can think of this $n{-}1$-category
       
  1164 as the 2-ended tensor product of the two bimodules associated to the two intervals.
       
  1165 
       
  1166 \medskip
       
  1167 
       
  1168 Next we define $n$-category 1-sphere modules.
       
  1169 These are just representations of (modules for) $n{-}1$-categories associated to marked and labeled 
       
  1170 circles (1-spheres) which we just introduced.
       
  1171 
       
  1172 Equivalently, we can define 1-sphere modules in terms of 1-marked $k$-balls, $2\le k\le n$.
       
  1173 Fix a marked (and labeled) circle $S$.
       
  1174 Let $C(S)$ denote the cone of $S$, a marked 2-ball (Figure xxxx).
       
  1175 \nn{I need to make up my mind whether marked things are always labeled too.}
       
  1176 A 1-marked $k$-ball is anything homeomorphic to $B^j \times C(S)$, $0\le j\le n-2$.
  1141 
  1177 
  1142 \medskip
  1178 \medskip
  1143 \hrule
  1179 \hrule
  1144 \medskip
  1180 \medskip
  1145 
  1181