diff -r 7b4f5e36d9de -r f8d909559d19 text/intro.tex --- a/text/intro.tex Tue Oct 20 18:25:54 2009 +0000 +++ b/text/intro.tex Thu Oct 22 04:08:49 2009 +0000 @@ -2,7 +2,30 @@ \section{Introduction} -[Outline for intro] +[some things to cover in the intro] +\begin{itemize} +\item explain relation between old and new blob complex definitions +\item overview of sections +\item state main properties of blob complex (already mostly done below) +\item give multiple motivations/viewpoints for blob complex: (1) derived cat +version of TQFT Hilbert space; (2) generalization of Hochschild homology to higher $n$-cats; +(3) ? sort-of-obvious colimit type construction; +(4) ? a generalization of $C_*(\Maps(M, T))$ to the case where $T$ is +a category rather than a manifold +\item hope to apply to Kh, contact, (other examples?) in the future +\item ?? we have resisted the temptation +(actually, it was not a temptation) to state things in the greatest +generality possible +\item related: we are being unsophisticated from a homotopy theory point of +view and using chain complexes in many places where we could be by with spaces +\item ? one of the points we make (far) below is that there is not really much +difference between (a) systems of fields and local relations and (b) $n$-cats; +thus we tend to switch between talking in terms of one or the other +\end{itemize} + +\medskip\hrule\medskip + +[Old outline for intro] \begin{itemize} \item Starting point: TQFTs via fields and local relations. This gives a satisfactory treatment for semisimple TQFTs @@ -61,18 +84,20 @@ \hrule \bigskip -We then show that blob homology enjoys the following -\ref{property:gluing} properties. +We then show that blob homology enjoys the following properties. \begin{property}[Functoriality] \label{property:functoriality}% -Blob homology is functorial with respect to diffeomorphisms. That is, fixing an $n$-dimensional system of fields $\cF$ and local relations $\cU$, the association +Blob homology is functorial with respect to homeomorphisms. That is, +for fixed $n$-category / fields $\cC$, the association \begin{equation*} -X \mapsto \bc_*^{\cF,\cU}(X) +X \mapsto \bc_*^{\cC}(X) \end{equation*} -is a functor from $n$-manifolds and diffeomorphisms between them to chain complexes and isomorphisms between them. +is a functor from $n$-manifolds and homeomorphisms between them to chain complexes and isomorphisms between them. \end{property} +\nn{should probably also say something about being functorial in $\cC$} + \begin{property}[Disjoint union] \label{property:disjoint-union} The blob complex of a disjoint union is naturally the tensor product of the blob complexes. @@ -81,13 +106,19 @@ \end{equation*} \end{property} -\begin{property}[A map for gluing] +\begin{property}[Gluing map] \label{property:gluing-map}% If $X_1$ and $X_2$ are $n$-manifolds, with $Y$ a codimension $0$-submanifold of $\bdy X_1$, and $Y^{\text{op}}$ a codimension $0$-submanifold of $\bdy X_2$, there is a chain map \begin{equation*} \gl_Y: \bc_*(X_1) \tensor \bc_*(X_2) \to \bc_*(X_1 \cup_Y X_2). \end{equation*} +\nn{alternate version:}Given a gluing $X_\mathrm{cut} \to X_\mathrm{gl}$, there is +a natural map +\[ + \bc_*(X_\mathrm{cut}) \to \bc_*(X_\mathrm{gl}) . +\] +(Natural with respect to homeomorphisms, and also associative with respect to iterated gluings.) \end{property} \begin{property}[Contractibility] @@ -104,9 +135,9 @@ \label{property:skein-modules}% The $0$-th blob homology of $X$ is the usual (dual) TQFT Hilbert space (a.k.a.\ skein module) associated to $X$ -by $(\cF,\cU)$. (See \S \ref{sec:local-relations}.) +by $\cC$. (See \S \ref{sec:local-relations}.) \begin{equation*} -H_0(\bc_*^{\cF,\cU}(X)) \iso A^{\cF,\cU}(X) +H_0(\bc_*^{\cC}(X)) \iso A^{\cC}(X) \end{equation*} \end{property}