# HG changeset patch # User kevin@6e1638ff-ae45-0410-89bd-df963105f760 # Date 1208799677 0 # Node ID 8599e156a169f303d7ce6fd76f5b761c261b282f # Parent 1b441b3595c9ce4b9b2151eeb9f883f402d6741e misc. edit, nothing major diff -r 1b441b3595c9 -r 8599e156a169 blob1.pdf Binary file blob1.pdf has changed diff -r 1b441b3595c9 -r 8599e156a169 blob1.tex --- a/blob1.tex Tue Mar 04 16:33:23 2008 +0000 +++ b/blob1.tex Mon Apr 21 17:41:17 2008 +0000 @@ -4,7 +4,7 @@ \usepackage[all]{xy} -% test edit #2 +% test edit #3 %%%%% excerpts from my include file of standard macros @@ -163,14 +163,20 @@ interior of $S$, each transversely oriented and each labeled by an element (1-morphism) of the algebra. -For $n=2$, a field on a 0-manifold $P$ is a labeling of each point of $P$ with +\medskip + +For $n=2$, fields are just the sort of pictures based on 2-categories (e.g.\ tensor categories) +that are common in the literature. +We describe these carefully here. + +A field on a 0-manifold $P$ is a labeling of each point of $P$ with an object of the 2-category $C$. A field of a 1-manifold is defined as in the $n=1$ case, using the 0- and 1-morphisms of $C$. A field on a 2-manifold $Y$ consists of \begin{itemize} \item A cell decomposition of $Y$ (equivalently, a graph embedded in $Y$ such that each component of the complement is homeomorphic to a disk); - \item a labeling of each 2-cell (and each half 2-cell adjacent to $\bd Y$) + \item a labeling of each 2-cell (and each partial 2-cell adjacent to $\bd Y$) by a 0-morphism of $C$; \item a transverse orientation of each 1-cell, thought of as a choice of ``domain" and ``range" for the two adjacent 2-cells; @@ -195,9 +201,11 @@ domain and range determined by the labelings of the link of $j$-cell. \end{itemize} -\nn{next definition might need some work; I think linearity relations should -be treated differently (segregated) from other local relations, but I'm not sure -the next definition is the best way to do it} +%\nn{next definition might need some work; I think linearity relations should +%be treated differently (segregated) from other local relations, but I'm not sure +%the next definition is the best way to do it} + +\medskip For top dimensional ($n$-dimensional) manifolds, we're actually interested in the linearized space of fields. @@ -245,7 +253,10 @@ A {\it local relation} is a collection subspaces $U(B^n; c) \sub \cC_l(B^n; c)$ (for all $c \in \cC(\bd B^n)$) satisfying the following (three?) properties. -\nn{implies (extended?) isotopy; stable under gluing; open covers?; ...} +\nn{Roughly, these are (1) the local relations imply (extended) isotopy; +(2) $U(B^n; \cdot)$ is an ideal w.r.t.\ gluing; and +(3) this ideal is generated by ``small" generators (contained in an open cover of $B^n$). +See KW TQFT notes for details. Need to transfer details to here.} For maps into spaces, $U(B^n; c)$ is generated by things of the form $a-b \in \cC_l(B^n; c)$, where $a$ and $b$ are maps (fields) which are homotopic rel boundary. @@ -259,6 +270,8 @@ Note that the $Y$ is an $n$-manifold which is merely homeomorphic to the standard $B^n$, then any homeomorphism $B^n \to Y$ induces the same local subspaces for $Y$. We'll denote these by $U(Y; c) \sub \cC_l(Y; c)$, $c \in \cC(\bd Y)$. +\nn{Is this true in high (smooth) dimensions? Self-diffeomorphisms of $B^n$ +rel boundary might not be isotopic to the identity. OK for PL and TOP?} Given a system of fields and local relations, we define the skein space $A(Y^n; c)$ to be the space of all finite linear combinations of fields on @@ -316,7 +329,7 @@ just erasing the blob from the picture (but keeping the blob label $u$). -Note that the skein module $A(X)$ +Note that the skein space $A(X)$ is naturally isomorphic to $\bc_0(X)/\bd(\bc_1(X))) = H_0(\bc_*(X))$. $\bc_2(X)$ is the space of all relations (redundancies) among the relations of $\bc_1(X)$. @@ -401,7 +414,7 @@ (Alert readers will have noticed that for $k=2$ our definition of $\bc_k(X)$ is slightly different from the previous definition -of $\bc_2(X)$. +of $\bc_2(X)$ --- we did not impose the reordering relations. The general definition takes precedence; the earlier definition was simplified for purposes of exposition.) @@ -424,8 +437,9 @@ \nn{?? say something about the ``shape" of tree? (incl = cone, disj = product)} -\nn{TO DO: ((?)) allow $n$-morphisms to be chain complex instead of just -a vector space; relations to Chas-Sullivan string stuff} +\nn{TO DO: +expand definition to handle DGA and $A_\infty$ versions of $n$-categories; +relations to Chas-Sullivan string stuff} @@ -493,6 +507,21 @@ \end{prop} +% oops -- duplicate + +%\begin{prop} \label{functorialprop} +%The assignment $X \mapsto \bc_*(X)$ extends to a functor from the category of +%$n$-manifolds and homeomorphisms to the category of chain complexes and linear isomorphisms. +%\end{prop} + +%\begin{proof} +%Obvious. +%\end{proof} + +%\nn{need to same something about boundaries and boundary conditions above. +%maybe fix the boundary and consider the category of $n$-manifolds with the given boundary.} + + \begin{prop} For fixed fields ($n$-cat), $\bc_*$ is a functor from the category of $n$-manifolds and diffeomorphisms to the category of chain complexes and @@ -500,6 +529,9 @@ \qed \end{prop} +\nn{need to same something about boundaries and boundary conditions above. +maybe fix the boundary and consider the category of $n$-manifolds with the given boundary.} + In particular, \begin{prop} \label{diff0prop}