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   376 with all the structure maps above (disjoint union, boundary restriction, etc.)
   376 with all the structure maps above (disjoint union, boundary restriction, etc.)
   377 Furthermore, if $f: Y\times I \to Y\times I$ is a fiber-preserving homeomorphism
   377 Furthermore, if $f: Y\times I \to Y\times I$ is a fiber-preserving homeomorphism
   378 covering $\bar{f}:Y\to Y$, then $f(c\times I) = \bar{f}(c)\times I$.
   378 covering $\bar{f}:Y\to Y$, then $f(c\times I) = \bar{f}(c)\times I$.
   379 \end{enumerate}
   379 \end{enumerate}
   380 
   380 
       
   381 \bigskip
       
   382 Using the functoriality and $\bullet\times I$ properties above, together
       
   383 with boundary collar homeomorphisms of manifolds, we can define the notion of 
       
   384 {\it extended isotopy}.
       
   385 Let $M$ be an $n$-manifold and $Y \subset \bd M$ be a codimension zero submanifold
       
   386 of $\bd M$.
       
   387 Let $x \in \cC(M)$ be a field on $M$ and such that $\bd x$ is cuttable along $\bd Y$.
       
   388 Let $c$ be $x$ restricted to $Y$.
       
   389 Let $M \cup (Y\times I)$ denote $M$ glued to $Y\times I$ along $Y$.
       
   390 Then we have the glued field $x \cup (c\times I)$ on $M \cup (Y\times I)$.
       
   391 Let $f: M \cup (Y\times I) \to M$ be a collaring homeomorphism.
       
   392 Then we say that $x$ is {\it extended isotopic} to $f(x \cup (c\times I))$.
       
   393 More generally, we define extended isotopy to be the equivalence relation on fields
       
   394 on $M$ generated by isotopy plus all instance of the above construction
       
   395 (for all appropriate $Y$ and $x$).
       
   396 
       
   397 \nn{should also say something about pseudo-isotopy}
   381 
   398 
   382 \bigskip
   399 \bigskip
   383 \hrule
   400 \hrule
   384 \bigskip
   401 \bigskip
   385 
   402 
   519 
   536 
   520 
   537 
   521 \subsection{Local relations}
   538 \subsection{Local relations}
   522 \label{sec:local-relations}
   539 \label{sec:local-relations}
   523 
   540 
   524 \nn{the following is not done yet}
   541 
   525 
   542 A {\it local relation} is a collection subspaces $U(B; c) \sub \c[\cC_l(B; c)]$
   526 Let $B^n$ denote the standard $n$-ball.
   543 (for all $n$-manifolds $B$ which are
   527 A {\it local relation} is a collection subspaces $U(B^n; c) \sub \cC_l(B^n; c)$
   544 homeomorphic to the standard $n$-ball and 
   528 (for all $c \in \cC(\bd B^n)$) satisfying the following two properties.
   545 all $c \in \cC(\bd B)$) satisfying the following properties.
   529 \begin{enumerate}
   546 \begin{enumerate}
   530 \item local relations imply (extended) isotopy \nn{...}
   547 \item functoriality: 
   531 \item $U(B^n; \cdot)$ is an ideal w.r.t.\ gluing \nn{...}
   548 $f(U(B; c)) = U(B', f(c))$ for all homeomorphisms $f: B \to B'$
       
   549 \item local relations imply extended isotopy: 
       
   550 if $x, y \in \cC(B; c)$ and $x$ is extended isotopic 
       
   551 to $y$, then $x-y \in U(B; c)$.
       
   552 \item ideal with respect to gluing:
       
   553 if $B = B' \cup B''$, $x\in U(B')$, and $c\in \cC(B'')$, then $x\cup r \in U(B)$
   532 \end{enumerate}
   554 \end{enumerate}
   533 See \cite{kw:tqft} for details.
   555 See \cite{kw:tqft} for details.
   534 
   556 
   535 
   557 
   536 For maps into spaces, $U(B^n; c)$ is generated by things of the form $a-b \in \cC_l(B^n; c)$,
   558 For maps into spaces, $U(B; c)$ is generated by things of the form $a-b \in \cC_l(B; c)$,
   537 where $a$ and $b$ are maps (fields) which are homotopic rel boundary.
   559 where $a$ and $b$ are maps (fields) which are homotopic rel boundary.
   538 
   560 
   539 For $n$-category pictures, $U(B^n; c)$ is equal to the kernel of the evaluation map
   561 For $n$-category pictures, $U(B; c)$ is equal to the kernel of the evaluation map
   540 $\cC_l(B^n; c) \to \mor(c', c'')$, where $(c', c'')$ is some (any) division of $c$ into
   562 $\cC_l(B; c) \to \mor(c', c'')$, where $(c', c'')$ is some (any) division of $c$ into
   541 domain and range.
   563 domain and range.
   542 
   564 
   543 \nn{maybe examples of local relations before general def?}
   565 \nn{maybe examples of local relations before general def?}
   544 
       
   545 Note that the $Y$ is an $n$-manifold which is merely homeomorphic to the standard $B^n$,
       
   546 then any homeomorphism $B^n \to Y$ induces the same local subspaces for $Y$.
       
   547 We'll denote these by $U(Y; c) \sub \cC_l(Y; c)$, $c \in \cC(\bd Y)$.
       
   548 \nn{Is this true in high (smooth) dimensions?  Self-diffeomorphisms of $B^n$
       
   549 rel boundary might not be isotopic to the identity.  OK for PL and TOP?}
       
   550 
   566 
   551 Given a system of fields and local relations, we define the skein space
   567 Given a system of fields and local relations, we define the skein space
   552 $A(Y^n; c)$ to be the space of all finite linear combinations of fields on
   568 $A(Y^n; c)$ to be the space of all finite linear combinations of fields on
   553 the $n$-manifold $Y$ modulo local relations.
   569 the $n$-manifold $Y$ modulo local relations.
   554 The Hilbert space $Z(Y; c)$ for the TQFT based on the fields and local relations
   570 The Hilbert space $Z(Y; c)$ for the TQFT based on the fields and local relations