text/ncat.tex
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   190 which is natural with respect to the actions of homeomorphisms.
   190 which is natural with respect to the actions of homeomorphisms.
   191 (When $k=1$ we stipulate that $\cl{\cC}(E)$ is a point, so that the above fibered product
   191 (When $k=1$ we stipulate that $\cl{\cC}(E)$ is a point, so that the above fibered product
   192 becomes a normal product.)
   192 becomes a normal product.)
   193 \end{lem}
   193 \end{lem}
   194 
   194 
   195 \begin{figure}[!ht] \centering
   195 \begin{figure}[t] \centering
   196 \begin{tikzpicture}[%every label/.style={green}
   196 \begin{tikzpicture}[%every label/.style={green}
   197 ]
   197 ]
   198 \node[fill=black, circle, label=below:$E$, inner sep=1.5pt](S) at (0,0) {};
   198 \node[fill=black, circle, label=below:$E$, inner sep=1.5pt](S) at (0,0) {};
   199 \node[fill=black, circle, label=above:$E$, inner sep=1.5pt](N) at (0,2) {};
   199 \node[fill=black, circle, label=above:$E$, inner sep=1.5pt](N) at (0,2) {};
   200 \draw (S) arc  (-90:90:1);
   200 \draw (S) arc  (-90:90:1);
   262 or if $k=n$ and we are in the $A_\infty$ case, 
   262 or if $k=n$ and we are in the $A_\infty$ case, 
   263 we require that $\gl_Y$ is injective.
   263 we require that $\gl_Y$ is injective.
   264 (For $k=n$ in the ordinary (non-$A_\infty$) case, see below.)
   264 (For $k=n$ in the ordinary (non-$A_\infty$) case, see below.)
   265 \end{axiom}
   265 \end{axiom}
   266 
   266 
   267 \begin{figure}[!ht] \centering
   267 \begin{figure}[t] \centering
   268 \begin{tikzpicture}[%every label/.style={green},
   268 \begin{tikzpicture}[%every label/.style={green},
   269 				x=1.5cm,y=1.5cm]
   269 				x=1.5cm,y=1.5cm]
   270 \node[fill=black, circle, label=below:$E$, inner sep=2pt](S) at (0,0) {};
   270 \node[fill=black, circle, label=below:$E$, inner sep=2pt](S) at (0,0) {};
   271 \node[fill=black, circle, label=above:$E$, inner sep=2pt](N) at (0,2) {};
   271 \node[fill=black, circle, label=above:$E$, inner sep=2pt](N) at (0,2) {};
   272 \draw (S) arc  (-90:90:1);
   272 \draw (S) arc  (-90:90:1);
   283 Given any splitting of a ball $B$ into smaller balls
   283 Given any splitting of a ball $B$ into smaller balls
   284 $$\bigsqcup B_i \to B,$$ 
   284 $$\bigsqcup B_i \to B,$$ 
   285 any sequence of gluings (in the sense of Definition \ref{defn:gluing-decomposition}, where all the intermediate steps are also disjoint unions of balls) yields the same result.
   285 any sequence of gluings (in the sense of Definition \ref{defn:gluing-decomposition}, where all the intermediate steps are also disjoint unions of balls) yields the same result.
   286 \end{axiom}
   286 \end{axiom}
   287 
   287 
   288 \begin{figure}[!ht]
   288 \begin{figure}[t]
   289 $$\mathfig{.65}{ncat/strict-associativity}$$
   289 $$\mathfig{.65}{ncat/strict-associativity}$$
   290 \caption{An example of strict associativity.}\label{blah6}\end{figure}
   290 \caption{An example of strict associativity.}\label{blah6}\end{figure}
   291 
   291 
   292 We'll use the notation  $a\bullet b$ for the glued together field $\gl_Y(a, b)$.
   292 We'll use the notation  $a\bullet b$ for the glued together field $\gl_Y(a, b)$.
   293 In the other direction, we will call the projection from $\cC(B)\trans E$ to $\cC(B_i)\trans E$ 
   293 In the other direction, we will call the projection from $\cC(B)\trans E$ to $\cC(B_i)\trans E$ 
   321 map from an appropriate subset (like a fibered product) 
   321 map from an appropriate subset (like a fibered product) 
   322 of $\cC(B_1)\spl\times\cdots\times\cC(B_m)\spl$ to $\cC(B)\spl$,
   322 of $\cC(B_1)\spl\times\cdots\times\cC(B_m)\spl$ to $\cC(B)\spl$,
   323 and these various $m$-fold composition maps satisfy an
   323 and these various $m$-fold composition maps satisfy an
   324 operad-type strict associativity condition (Figure \ref{fig:operad-composition}).}
   324 operad-type strict associativity condition (Figure \ref{fig:operad-composition}).}
   325 
   325 
   326 \begin{figure}[!ht]
   326 \begin{figure}[t]
   327 $$\mathfig{.8}{ncat/operad-composition}$$
   327 $$\mathfig{.8}{ncat/operad-composition}$$
   328 \caption{Operad composition and associativity}\label{fig:operad-composition}\end{figure}
   328 \caption{Operad composition and associativity}\label{fig:operad-composition}\end{figure}
   329 
   329 
   330 The next axiom is related to identity morphisms, though that might not be immediately obvious.
   330 The next axiom is related to identity morphisms, though that might not be immediately obvious.
   331 
   331 
   586 \begin{eqnarray*}
   586 \begin{eqnarray*}
   587 	\psi_{Y,J}: \cC(X) &\to& \cC(X) \\
   587 	\psi_{Y,J}: \cC(X) &\to& \cC(X) \\
   588 	a & \mapsto & s_{Y,J}(a \cup ((a|_Y)\times J)) .
   588 	a & \mapsto & s_{Y,J}(a \cup ((a|_Y)\times J)) .
   589 \end{eqnarray*}
   589 \end{eqnarray*}
   590 (See Figure \ref{glue-collar}.)
   590 (See Figure \ref{glue-collar}.)
   591 \begin{figure}[!ht]
   591 \begin{figure}[t]
   592 \begin{equation*}
   592 \begin{equation*}
   593 \begin{tikzpicture}
   593 \begin{tikzpicture}
   594 \def\rad{1}
   594 \def\rad{1}
   595 \def\srad{0.75}
   595 \def\srad{0.75}
   596 \def\gap{4.5}
   596 \def\gap{4.5}
   835 to be the dual Hilbert space $A(X\times F; c)$.
   835 to be the dual Hilbert space $A(X\times F; c)$.
   836 (See \S\ref{sec:constructing-a-tqft}.)
   836 (See \S\ref{sec:constructing-a-tqft}.)
   837 \end{example}
   837 \end{example}
   838 
   838 
   839 
   839 
   840 \begin{example}[The bordism $n$-category of $d$-manifolds, ordinary version]
   840 \begin{example}[te bordism $n$-category of $d$-manifolds, ordinary version]
   841 \label{ex:bord-cat}
   841 \label{ex:bord-cat}
   842 \rm
   842 \rm
   843 \label{ex:bordism-category}
   843 \label{ex:bordism-category}
   844 For a $k$-ball $X$, $k<n$, define $\Bord^{n,d}(X)$ to be the set of all $(d{-}n{+}k)$-dimensional PL
   844 For a $k$-ball $X$, $k<n$, define $\Bord^{n,d}(X)$ to be the set of all $(d{-}n{+}k)$-dimensional PL
   845 submanifolds $W$ of $X\times \Real^\infty$ such that $\bd W = W \cap \bd X \times \Real^\infty$.
   845 submanifolds $W$ of $X\times \Real^\infty$ such that $\bd W = W \cap \bd X \times \Real^\infty$.
   910 is not the $A_\infty$ $n$-category $\pi^\infty_{\leq n}(T)$.
   910 is not the $A_\infty$ $n$-category $\pi^\infty_{\leq n}(T)$.
   911 It's easy to see that with $n=0$, the corresponding system of fields is just 
   911 It's easy to see that with $n=0$, the corresponding system of fields is just 
   912 linear combinations of connected components of $T$, and the local relations are trivial.
   912 linear combinations of connected components of $T$, and the local relations are trivial.
   913 There's no way for the blob complex to magically recover all the data of $\pi^\infty_{\leq 0}(T) \iso C_* T$.
   913 There's no way for the blob complex to magically recover all the data of $\pi^\infty_{\leq 0}(T) \iso C_* T$.
   914 
   914 
   915 \begin{example}[The bordism $n$-category of $d$-manifolds, $A_\infty$ version]
   915 \begin{example}[te bordism $n$-category of $d$-manifolds, $A_\infty$ version]
   916 \rm
   916 \rm
   917 \label{ex:bordism-category-ainf}
   917 \label{ex:bordism-category-ainf}
   918 As in Example \ref{ex:bord-cat}, for $X$ a $k$-ball, $k<n$, we define $\Bord^{n,d}_\infty(X)$
   918 As in Example \ref{ex:bord-cat}, for $X$ a $k$-ball, $k<n$, we define $\Bord^{n,d}_\infty(X)$
   919 to be the set of all $(d{-}n{+}k)$-dimensional
   919 to be the set of all $(d{-}n{+}k)$-dimensional
   920 submanifolds $W$ of $X\times \Real^\infty$ such that $\bd W = W \cap \bd X \times \Real^\infty$.
   920 submanifolds $W$ of $X\times \Real^\infty$ such that $\bd W = W \cap \bd X \times \Real^\infty$.
  1043 The poset $\cell(W)$ has objects the permissible decompositions of $W$, 
  1043 The poset $\cell(W)$ has objects the permissible decompositions of $W$, 
  1044 and a unique morphism from $x$ to $y$ if and only if $x$ is a refinement of $y$.
  1044 and a unique morphism from $x$ to $y$ if and only if $x$ is a refinement of $y$.
  1045 See Figure \ref{partofJfig} for an example.
  1045 See Figure \ref{partofJfig} for an example.
  1046 \end{defn}
  1046 \end{defn}
  1047 
  1047 
  1048 \begin{figure}[!ht]
  1048 \begin{figure}[t]
  1049 \begin{equation*}
  1049 \begin{equation*}
  1050 \mathfig{.63}{ncat/zz2}
  1050 \mathfig{.63}{ncat/zz2}
  1051 \end{equation*}
  1051 \end{equation*}
  1052 \caption{A small part of $\cell(W)$}
  1052 \caption{A small part of $\cell(W)$}
  1053 \label{partofJfig}
  1053 \label{partofJfig}
  1274 (see Example \ref{ex:maps-with-fiber}).
  1274 (see Example \ref{ex:maps-with-fiber}).
  1275 (The union is along $N\times \bd W$.)
  1275 (The union is along $N\times \bd W$.)
  1276 %(If $\cD$ were a general TQFT, we would define $\cM(B, N)$ to be
  1276 %(If $\cD$ were a general TQFT, we would define $\cM(B, N)$ to be
  1277 %the subset of $\cD((B\times \bd W)\cup (N\times W))$ which is splittable along $N\times \bd W$.)
  1277 %the subset of $\cD((B\times \bd W)\cup (N\times W))$ which is splittable along $N\times \bd W$.)
  1278 
  1278 
  1279 \begin{figure}[!ht]
  1279 \begin{figure}[t]
  1280 $$\mathfig{.55}{ncat/boundary-collar}$$
  1280 $$\mathfig{.55}{ncat/boundary-collar}$$
  1281 \caption{From manifold with boundary collar to marked ball}\label{blah15}\end{figure}
  1281 \caption{From manifold with boundary collar to marked ball}\label{blah15}\end{figure}
  1282 
  1282 
  1283 Define the boundary of a marked $k$-ball $(B, N)$ to be the pair $(\bd B \setmin N, \bd N)$.
  1283 Define the boundary of a marked $k$-ball $(B, N)$ to be the pair $(\bd B \setmin N, \bd N)$.
  1284 Call such a thing a {marked $k{-}1$-hemisphere}.
  1284 Call such a thing a {marked $k{-}1$-hemisphere}.
  1340 
  1340 
  1341 We require two sorts of composition (gluing) for modules, corresponding to two ways
  1341 We require two sorts of composition (gluing) for modules, corresponding to two ways
  1342 of splitting a marked $k$-ball into two (marked or plain) $k$-balls.
  1342 of splitting a marked $k$-ball into two (marked or plain) $k$-balls.
  1343 (See Figure \ref{zzz3}.)
  1343 (See Figure \ref{zzz3}.)
  1344 
  1344 
  1345 \begin{figure}[!ht]
  1345 \begin{figure}[t]
  1346 \begin{equation*}
  1346 \begin{equation*}
  1347 \mathfig{.4}{ncat/zz3}
  1347 \mathfig{.4}{ncat/zz3}
  1348 \end{equation*}
  1348 \end{equation*}
  1349 \caption{Module composition (top); $n$-category action (bottom).}
  1349 \caption{Module composition (top); $n$-category action (bottom).}
  1350 \label{zzz3}
  1350 \label{zzz3}
  1403 
  1403 
  1404 Note that the above associativity axiom applies to mixtures of module composition,
  1404 Note that the above associativity axiom applies to mixtures of module composition,
  1405 action maps and $n$-category composition.
  1405 action maps and $n$-category composition.
  1406 See Figure \ref{zzz1b}.
  1406 See Figure \ref{zzz1b}.
  1407 
  1407 
  1408 \begin{figure}[!ht]
  1408 \begin{figure}[t]
  1409 \begin{equation*}
  1409 \begin{equation*}
  1410 \mathfig{0.49}{ncat/zz0} \mathfig{0.49}{ncat/zz1}
  1410 \mathfig{0.49}{ncat/zz0} \mathfig{0.49}{ncat/zz1}
  1411 \end{equation*}
  1411 \end{equation*}
  1412 \caption{Two examples of mixed associativity}
  1412 \caption{Two examples of mixed associativity}
  1413 \label{zzz1b}
  1413 \label{zzz1b}