text/a_inf_blob.tex
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    13 When we need to distinguish between the new and old definitions, we will refer to the 
    13 When we need to distinguish between the new and old definitions, we will refer to the 
    14 new-fangled and old-fashioned blob complex.
    14 new-fangled and old-fashioned blob complex.
    15 
    15 
    16 \medskip
    16 \medskip
    17 
    17 
    18 \subsection{The small blob complex}
    18 An important technical tool in the proofs of this section is provided by the idea of `small blobs'.
    19 
    19 Fix $\cU$, an open cover of $M$. Define the `small blob complex' $\bc^{\cU}_*(M)$ to be the subcomplex of $\bc_*(M)$ of all blob diagrams in which every blob is contained in some open set of $\cU$. 
    20 \input{text/smallblobs}
    20 \nn{KW: We need something a little stronger: Every blob diagram (even a 0-blob diagram) is splittable into pieces which are small w.r.t.\ $\cU$.
       
    21 If field have potentially large coupons/boxes, then this is a non-trivial constraint.
       
    22 On the other hand, we could probably get away with ignoring this point.
       
    23 Maybe the exposition will be better if we sweep this technical detail under the rug?}
       
    24 
       
    25 \begin{thm}[Small blobs] \label{thm:small-blobs}
       
    26 The inclusion $i: \bc^{\cU}_*(M) \into \bc_*(M)$ is a homotopy equivalence.
       
    27 \end{thm}
       
    28 The proof appears in \S \ref{appendix:small-blobs}.
    21 
    29 
    22 \subsection{A product formula}
    30 \subsection{A product formula}
    23 \label{ss:product-formula}
    31 \label{ss:product-formula}
    24 
    32 
    25 \noop{
    33 \noop{