text/intro.tex
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    32 In  \S \ref{sec:ainfblob} we explain how to construct a system of fields from a topological $n$-category, and give an alternative definition of the blob complex for an $A_\infty$ $n$-category on an $n$-manifold. Using these definitions, we show how to use the blob complex to `resolve' any topological $n$-category as an $A_\infty$ $n$-category, and relate the first and second definitions of the blob complex. We use the blob complex for $A_\infty$ $n$-categories to establish important properties of the blob complex (in both variants), in particular the `gluing formula' of Property \ref{property:gluing} below.
    32 In  \S \ref{sec:ainfblob} we explain how to construct a system of fields from a topological $n$-category, and give an alternative definition of the blob complex for an $A_\infty$ $n$-category on an $n$-manifold. Using these definitions, we show how to use the blob complex to `resolve' any topological $n$-category as an $A_\infty$ $n$-category, and relate the first and second definitions of the blob complex. We use the blob complex for $A_\infty$ $n$-categories to establish important properties of the blob complex (in both variants), in particular the `gluing formula' of Property \ref{property:gluing} below.
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    34 \nn{KW: the previous two paragraphs seem a little awkward to me, but I don't presently have a good idea for fixing them.}
    34 \nn{KW: the previous two paragraphs seem a little awkward to me, but I don't presently have a good idea for fixing them.}
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    36 Finally, later sections address other topics. Section \S \ref{sec:comm_alg} describes the blob complex when $\cC$ is a commutative algebra, thought of as a topological $n$-category, in terms of the topology of $M$. Section \S \ref{sec:deligne} states (and in a later edition of this paper, hopefully proves) a higher dimensional generalisation of the Deligne conjecture (that the little discs operad acts on Hochschild cohomology) in terms of the blob complex. The appendixes prove technical results about $\CH{M}$, and make connections between our definitions of $n$-categories and familar definitions for $n=1$ and $n=2$, as well as relating the $n=1$ case of our $A_\infty$ $n$-categories with usual $A_\infty$ algebras.
    36 \tikzstyle{box} = [rectangle, rounded corners, draw,outer sep = 5pt, inner sep = 5pt, line width=0.5pt]
       
    37 
       
    38 {\center
       
    39 
       
    40 \begin{tikzpicture}[align=center,line width = 1.5pt]
       
    41 \newcommand{\xa}{2}
       
    42 \newcommand{\xb}{10}
       
    43 \newcommand{\ya}{14}
       
    44 \newcommand{\yb}{10}
       
    45 \newcommand{\yc}{6}
       
    46 
       
    47 \node[box] at (\xa,\ya) (C) {$\cC$ \\ a topological \\ $n$-category};
       
    48 \node[box] at (\xb,\ya) (A) {$A(M; \cC)$ \\ the (dual) TQFT \\ Hilbert space};
       
    49 \node[box] at (\xa,\yb) (FU) {$(\cF, \cU)$ \\ fields and\\ local relations};
       
    50 \node[box] at (\xb,\yb) (BC) {$\bc_*(M; \cC)$ \\ the blob complex};
       
    51 \node[box] at (\xa,\yc) (Cs) {$\cC_*$ \\ an $A_\infty$ \\$n$-category};
       
    52 \node[box] at (\xb,\yc) (BCs) {$\bc_*(M; \cC_*)$};
       
    53 
       
    54 
       
    55 
       
    56 \draw[->] (C) -- node[above] {$\displaystyle \colim_{\cell(M)} \cC$} (A);
       
    57 \draw[->] (FU) -- node[below] {blob complex \\ for $M$} (BC);
       
    58 \draw[->] (Cs) -- node[below] {$\displaystyle \hocolim_{\cell(M)} \cC_*$} (BCs);
       
    59 
       
    60 \draw[->] (FU) -- node[right=10pt] {$\cF(M)/\cU$} (A);
       
    61 
       
    62 \draw[->] (C) -- node[left=10pt,align=left] {
       
    63 	%$\displaystyle \cF(M) = \DirectSum_{c \in\cell(M)} \cC(c)$ \\ $\displaystyle \cU(B) = \DirectSum_{c \in \cell(B)} \ker \ev: \cC(c) \to \cC(B)$
       
    64    } (FU);
       
    65 \draw[->] (BC) -- node[right] {$H_0$} (A);
       
    66 
       
    67 \draw[->] (FU) -- node[left] {blob complex \\ for balls} (Cs);
       
    68 \draw (BC) -- node[right] {$\iso$ by \\ Corollary \ref{cor:new-old}} (BCs);
       
    69 \end{tikzpicture}
       
    70 
       
    71 }
       
    72 
       
    73 Finally, later sections address other topics. Section \S \ref{sec:comm_alg} describes the blob complex when $\cC$ is a commutative algebra, thought of as a topological $n$-category, in terms of the topology of $M$. Section \S \ref{sec:deligne} states (and in a later edition of this paper, hopefully proves) a higher dimensional generalization of the Deligne conjecture (that the little discs operad acts on Hochschild cohomology) in terms of the blob complex. The appendixes prove technical results about $\CH{M}$, and make connections between our definitions of $n$-categories and familiar definitions for $n=1$ and $n=2$, as well as relating the $n=1$ case of our $A_\infty$ $n$-categories with usual $A_\infty$ algebras.
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    39 \nn{some more things to cover in the intro}
    76 \nn{some more things to cover in the intro}
    40 \begin{itemize}
    77 \begin{itemize}
    41 \item related: we are being unsophisticated from a homotopy theory point of
    78 \item related: we are being unsophisticated from a homotopy theory point of