diff -r af22fa790d13 -r 15a79fb469e1 blob1.tex --- a/blob1.tex Tue Mar 03 23:27:22 2009 +0000 +++ b/blob1.tex Thu Mar 12 19:53:43 2009 +0000 @@ -52,7 +52,7 @@ % \DeclareMathOperator{\pr}{pr} etc. \def\declaremathop#1{\expandafter\DeclareMathOperator\csname #1\endcsname{#1}} -\applytolist{declaremathop}{pr}{im}{gl}{ev}{coinv}{tr}{rot}{Eq}{obj}{mor}{ob}{Rep}{Tet}{cat}{Maps}{Diff}{sign}{supp}{maps}; +\applytolist{declaremathop}{pr}{im}{gl}{ev}{coinv}{tr}{rot}{Eq}{obj}{mor}{ob}{Rep}{Tet}{cat}{Maps}{Diff}{sign}{supp}; @@ -764,8 +764,7 @@ In the other direction, any blob diagram on $X\du Y$ is equal (up to sign) to one that puts $X$ blobs before $Y$ blobs in the ordering, and so determines a pair of blob diagrams on $X$ and $Y$. -These two maps are compatible with our sign conventions \nn{say more about this?} and -with the linear label relations. +These two maps are compatible with our sign conventions. The two maps are inverses of each other. \nn{should probably say something about sign conventions for the differential in a tensor product of chain complexes; ask Scott} @@ -778,7 +777,7 @@ we have a splitting $s: H_0(\bc_*(B^n, c)) \to \bc_0(B^n; c)$ of the quotient map $p: \bc_0(B^n; c) \to H_0(\bc_*(B^n, c))$. -\nn{always the case if we're working over $\c$}. +For example, this is always the case if you coefficient ring is a field. Then \begin{prop} \label{bcontract} For all $c \in \cC(\bd B^n)$ the natural map $p: \bc_*(B^n, c) \to H_0(\bc_*(B^n, c))$ @@ -794,20 +793,20 @@ In other words, add a new outermost blob which encloses all of the others. Define $h_0 : \bc_0(B^n; c) \to \bc_1(B^n; c)$ by setting $h_0(x)$ equal to the 1-blob with blob $B^n$ and label $x - s(p(x)) \in U(B^n; c)$. -\nn{$x$ is a 0-blob diagram, i.e. $x \in \cC(B^n; c)$} \end{proof} -(Note that for the above proof to work, we need the linear label relations -for blob labels. -Also we need to blob reordering relations (?).) +Note that if there is no splitting $s$, we can let $h_0 = 0$ and get a homotopy +equivalence to the 2-step complex $U(B^n; c) \to \cC(B^n; c)$. -(Note also that if there is no splitting $s$, we can let $h_0 = 0$ and get a homotopy -equivalence to the 2-step complex $U(B^n; c) \to \cC(B^n; c)$.) - -(For fields based on $n$-cats, $H_0(\bc_*(B^n; c)) \cong \mor(c', c'')$.) +For fields based on $n$-categories, $H_0(\bc_*(B^n; c)) \cong \mor(c', c'')$, +where $(c', c'')$ is some (any) splitting of $c$ into domain and range. \medskip +\nn{Maybe there is no longer a need to repeat the next couple of props here, since we also state them in the introduction. +But I think it's worth saying that the Diff actions will be enhanced later. +Maybe put that in the intro too.} + As we noted above, \begin{prop} There is a natural isomorphism $H_0(\bc_*(X)) \cong A(X)$. @@ -815,21 +814,6 @@ \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 @@ -837,10 +821,6 @@ \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} There is an action of $\Diff(X)$ on $\bc_*(X)$. @@ -857,7 +837,7 @@ Let $X$ be an $n$-manifold, $\bd X = Y \cup (-Y) \cup Z$. Gluing the two copies of $Y$ together yields an $n$-manifold $X\sgl$ with boundary $Z\sgl$. -Given compatible fields (pictures, boundary conditions) $a$, $b$ and $c$ on $Y$, $-Y$ and $Z$, +Given compatible fields (boundary conditions) $a$, $b$ and $c$ on $Y$, $-Y$ and $Z$, we have the blob complex $\bc_*(X; a, b, c)$. If $b = -a$ (the orientation reversal of $a$), then we can glue up blob diagrams on $X$ to get blob diagrams on $X\sgl$: @@ -876,6 +856,8 @@ The above map is very far from being an isomorphism, even on homology. This will be fixed in Section \ref{sec:gluing} below. +\nn{Next para not need, since we already use bullet = gluing notation above(?)} + An instance of gluing we will encounter frequently below is where $X = X_1 \du X_2$ and $X\sgl = X_1 \cup_Y X_2$. (Typically one of $X_1$ or $X_2$ is a disjoint union of balls.) @@ -886,9 +868,8 @@ Note that we have resumed our habit of omitting boundary labels from the notation. -\bigskip -\nn{what else?} + \section{Hochschild homology when $n=1$} \label{sec:hochschild}