# HG changeset patch # User scott@6e1638ff-ae45-0410-89bd-df963105f760 # Date 1227215310 0 # Node ID ead6bc1a703fd2ba2c4f6d7d90c8b1c15153bbb6 # Parent 90792b3b267b76888d87298a01f46104c40ed644 ... diff -r 90792b3b267b -r ead6bc1a703f blob1.tex --- a/blob1.tex Sun Nov 16 00:13:00 2008 +0000 +++ b/blob1.tex Thu Nov 20 21:08:30 2008 +0000 @@ -8,8 +8,6 @@ %%%%% excerpts from my include file of standard macros -\def\bc{{\mathcal B}} - \def\z{\mathbb{Z}} \def\r{\mathbb{R}} \def\c{\mathbb{C}} @@ -225,9 +223,8 @@ $X$ by gluing along $Y$, is the $A_\infty$ self-tensor product of $\bc_*(X)$ as an $\bc_*(Y \times I)$-bimodule. \begin{equation*} -\bc_*(X') \iso \bc_*(X) \Tensor^{A_\infty}_{\mathclap{\bc_*(Y \times I)}} +\bc_*(X') \iso \bc_*(X) \Tensor^{A_\infty}_{\mathclap{\bc_*(Y \times I)}} \!\!\!\!\!\!\xymatrix{ \ar@(ru,rd)@<-1ex>[]} \end{equation*} -\todo{How do you write self tensor product?} \end{itemize} \end{property} @@ -959,9 +956,8 @@ $X$ by gluing along $Y$, is the $A_\infty$ self-tensor product of $\bc_*(X)$ as an $\bc_*(Y \times I)$-bimodule. \begin{equation*} -\bc_*(X') \iso \bc_*(X) \Tensor^{A_\infty}_{\mathclap{\bc_*(Y \times I)}} +\bc_*(X') \iso \bc_*(X) \Tensor^{A_\infty}_{\mathclap{\bc_*(Y \times I)}} \!\!\!\!\!\!\xymatrix{ \ar@(ru,rd)@<-1ex>[]} \end{equation*} -\todo{How do you write self tensor product?} \end{itemize} Although this gluing formula is stated in terms of $A_\infty$ categories and their (bi-)modules, it will be more natural for us to give alternative diff -r 90792b3b267b -r ead6bc1a703f text/fields.tex --- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/text/fields.tex Thu Nov 20 21:08:30 2008 +0000 @@ -0,0 +1,36 @@ +\newcommand{\manifolds}[1]{\cM_{#1}} +\newcommand{\closedManifolds}[1]{\cM_{#1}^{\text{closed}}} +\newcommand{\boundaryConditions}[1]{\cM_{#1}^{\bdy}} +Let $\manifolds{k}$ be the groupoid of manifolds (possibly with boundary) of dimension $k$ and diffeomorphisms between them. Write +$\closedManifolds{k}$ for the subgroupoid of closed manifolds. Taking the boundary gives a functor $\bdy : \manifolds{k} \to \closedManifolds{k-1}$. +Both $\manifolds{k}$ and $\closedManifolds{k}$ are symmetric tensor categories under the operation of disjoint union. +\begin{defn} +A \emph{system of fields} is a collection of functors associating a `set of fields' to each manifold of dimension at most $n$. + +First, there are functors $\cC_k : \closedManifolds{k} \to \Set$ for each $0 \leq k < n$. We ask that these are tensor functors, so they +take disjoint unions of manifolds to cartesian products of sets. In particular, this means that $\cC_k(\eset)$ is a point; there's only one field +on the empty manifold of any dimension. + +Define the groupoid $\boundaryConditions{k}$ of `manifolds with boundary conditions' as +\begin{equation*} +\setc{(Y; c)}{\begin{array}{c} \text{$Y$ a $k$-manifold} \\ c \in \cC_{k-1}(\bdy Y) \end{array}} +\xymatrix{ \ar@(ru,rd)@<-1ex>[]} +\set{Y \diffeoto Y'} +\end{equation*} +where we think of $f: Y \diffeoto Y'$ as a morphism $(Y; c) \isoto (Y'; \cC_{k-1}(\restrict{f}{\bdy Y})(c))$. +% +%The objects are pairs $(Y; c)$ with $Y$ a manifold (possibly with boundary) of dimension $k$ and $c \in \cC_{k-1}(\bdy Y)$ +%a field on the boundary of $Y$. A morphism $(Y; c) \to (Y'; c')$ is any diffeomorphism $f: Y \to Y'$ such that $\cC_{k-1}(\restrict{f}{\bdy Y})(c) = c'$. +Notice that $\closedManifolds{k}$ is naturally a subgroupoid of $\boundaryConditions{k}$, since a closed manifold has a unique field on its (empty) boundary. + +We now ask that the functors $\cC_k$ above extend to functors $\cC_k : \boundaryConditions{k} \to \Set$ for each $0 \leq k < n$, +and that there is an extra functor at the top level, $\cC_n : \boundaryConditions{n} \to \Vect$. (Notice that for $n$-manifolds we ask for a vector space, not just a set. This isn't essential for the definition, but we will only be interested in this case hereafter.) +We still require that these are tensor functors, and so take disjoint unions of manifolds to cartesian products of sets, or tensor products of vector spaces, as appropriate. + +\scott{Not sure how to say product fields in this setup.} +Finally, notice there are functors $- \times I : \manifolds{k} \to \manifolds{k+1}$ +Finally (?) we ask for natural transformations $- \times I : \cC_k \to \cC_{k+1} \compose (- \times I)$. Thus for each pair $(Y^k; c)$ we have a map $\cC_k($ +\end{defn} +\begin{rem} +Where the dimension of the manifold is clear, we'll often leave off the subscript on $\cC_k$. +\end{rem}