text/evmap.tex
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    48 of the blob complex, and show that they are both homotopy equivalent to $\bc_*(X)$.
    48 of the blob complex, and show that they are both homotopy equivalent to $\bc_*(X)$.
    49 
    49 
    50 \medskip
    50 \medskip
    51 
    51 
    52 If $b$ is a blob diagram in $\bc_*(X)$, recall from \S \ref{sec:basic-properties} that the {\it support} of $b$, denoted
    52 If $b$ is a blob diagram in $\bc_*(X)$, recall from \S \ref{sec:basic-properties} that the {\it support} of $b$, denoted
    53 $\supp(b)$ or $|b|$, to be the union of the blobs of $b$.
    53 $\supp(b)$ or $|b|$, is the union of the blobs of $b$.
    54 %For a general $k$-chain $a\in \bc_k(X)$, define the support of $a$ to be the union
    54 %For a general $k$-chain $a\in \bc_k(X)$, define the support of $a$ to be the union
    55 %of the supports of the blob diagrams which appear in it.
    55 %of the supports of the blob diagrams which appear in it.
    56 More generally, we say that a chain $a\in \bc_k(X)$ is supported on $S$ if
    56 More generally, we say that a chain $a\in \bc_k(X)$ is supported on $S$ if
    57 $a = a'\bullet r$, where $a'\in \bc_k(S)$ and $r\in \bc_0(X\setmin S)$.
    57 $a = a'\bullet r$, where $a'\in \bc_k(S)$ and $r\in \bc_0(X\setmin S)$.
    58 
    58 
    62 We will sometimes abuse language and talk about ``the" support of $f$,
    62 We will sometimes abuse language and talk about ``the" support of $f$,
    63 again denoted $\supp(f)$ or $|f|$, to mean some particular choice of $Y$ such that
    63 again denoted $\supp(f)$ or $|f|$, to mean some particular choice of $Y$ such that
    64 $f$ is supported on $Y$.
    64 $f$ is supported on $Y$.
    65 
    65 
    66 If $f: M \cup (Y\times I) \to M$ is a collaring homeomorphism
    66 If $f: M \cup (Y\times I) \to M$ is a collaring homeomorphism
    67 (cf. end of \S \ref{ss:syst-o-fields}),
    67 (cf.\ the end of \S \ref{ss:syst-o-fields}),
    68 we say that $f$ is supported on $S\sub M$ if $f(x) = x$ for all $x\in M\setmin S$.
    68 we say that $f$ is supported on $S\sub M$ if $f(x) = x$ for all $x\in M\setmin S$.
    69 
    69 
    70 \medskip
    70 \medskip
    71 
    71 
    72 Fix $\cU$, an open cover of $X$.
    72 Fix $\cU$, an open cover of $X$.
    73 Define the ``small blob complex" $\bc^{\cU}_*(X)$ to be the subcomplex of $\bc_*(X)$ 
    73 Define the ``small blob complex" $\bc^{\cU}_*(X)$ to be the subcomplex of $\bc_*(X)$ 
    74 of all blob diagrams in which every blob is contained in some open set of $\cU$, 
    74 generated by blob diagrams such that every blob is contained in some open set of $\cU$, 
    75 and moreover each field labeling a region cut out by the blobs is splittable 
    75 and moreover each field labeling a region cut out by the blobs is splittable 
    76 into fields on smaller regions, each of which is contained in some open set of $\cU$.
    76 into fields on smaller regions, each of which is contained in some open set of $\cU$.
    77 
    77 
    78 \begin{lemma}[Small blobs] \label{small-blobs-b}  \label{thm:small-blobs}
    78 \begin{lemma}[Small blobs] \label{small-blobs-b}  \label{thm:small-blobs}
    79 The inclusion $i: \bc^{\cU}_*(X) \into \bc_*(X)$ is a homotopy equivalence.
    79 The inclusion $i: \bc^{\cU}_*(X) \into \bc_*(X)$ is a homotopy equivalence.
   112 Roughly speaking, $s(b)$ consists of a series of 1-blob diagrams implementing a series
   112 Roughly speaking, $s(b)$ consists of a series of 1-blob diagrams implementing a series
   113 of small collar maps, plus a shrunken version of $b$.
   113 of small collar maps, plus a shrunken version of $b$.
   114 The composition of all the collar maps shrinks $B$ to a ball which is small with respect to $\cU$.
   114 The composition of all the collar maps shrinks $B$ to a ball which is small with respect to $\cU$.
   115 
   115 
   116 Let $\cV_1$ be an auxiliary open cover of $X$, subordinate to $\cU$ and 
   116 Let $\cV_1$ be an auxiliary open cover of $X$, subordinate to $\cU$ and 
   117 fine enough that a condition stated later in the proof is satisfied.
   117 fine enough that a condition stated later in this proof is satisfied.
   118 Let $b = (B, u, r)$, with $u = \sum a_i$ the label of $B$, and $a_i\in \bc_0(B)$.
   118 Let $b = (B, u, r)$, with $u = \sum a_i$ the label of $B$, and $a_i\in \bc_0(B)$.
   119 Choose a sequence of collar maps $\bar{f}_j:B\cup\text{collar}\to B$ satisfying conditions 
   119 Choose a sequence of collar maps $\bar{f}_j:B\cup\text{collar}\to B$ satisfying conditions 
   120 specified at the end of this paragraph.
   120 specified at the end of this paragraph.
   121 Let $f_j:B\to B$ be the restriction of $\bar{f}_j$ to $B$; $f_j$ maps $B$ homeomorphically to 
   121 Let $f_j:B\to B$ be the restriction of $\bar{f}_j$ to $B$; $f_j$ maps $B$ homeomorphically to 
   122 a slightly smaller submanifold of $B$.
   122 a slightly smaller submanifold of $B$.
   424 \begin{thm}  \label{thm:CH} \label{thm:evaluation}%
   424 \begin{thm}  \label{thm:CH} \label{thm:evaluation}%
   425 For $n$-manifolds $X$ and $Y$ there is a chain map
   425 For $n$-manifolds $X$ and $Y$ there is a chain map
   426 \eq{
   426 \eq{
   427     e_{XY} : \CH{X \to Y} \otimes \bc_*(X) \to \bc_*(Y) ,
   427     e_{XY} : \CH{X \to Y} \otimes \bc_*(X) \to \bc_*(Y) ,
   428 }
   428 }
   429 well-defined up to (coherent) homotopy,
   429 well-defined up to coherent homotopy,
   430 such that
   430 such that
   431 \begin{enumerate}
   431 \begin{enumerate}
   432 \item on $C_0(\Homeo(X \to Y)) \otimes \bc_*(X)$ it agrees with the obvious action of 
   432 \item on $C_0(\Homeo(X \to Y)) \otimes \bc_*(X)$ it agrees with the obvious action of 
   433 $\Homeo(X, Y)$ on $\bc_*(X)$  described in Property \ref{property:functoriality}, and
   433 $\Homeo(X, Y)$ on $\bc_*(X)$  described in Property \ref{property:functoriality}, and
   434 \item for any compatible splittings $X\to X\sgl$ and $Y\to Y\sgl$, 
   434 \item for any compatible splittings $X\to X\sgl$ and $Y\to Y\sgl$,