text/evmap.tex
changeset 434 785e4953a811
parent 430 c5a35886cd82
child 438 0d62ea7c653d
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   120 To show existence, we must show that the various choices involved in constructing
   120 To show existence, we must show that the various choices involved in constructing
   121 evaluation maps in this way affect the final answer only by a homotopy.
   121 evaluation maps in this way affect the final answer only by a homotopy.
   122 
   122 
   123 Now for a little more detail.
   123 Now for a little more detail.
   124 (But we're still just motivating the full, gory details, which will follow.)
   124 (But we're still just motivating the full, gory details, which will follow.)
   125 Choose a metric on $X$, and let $\cU_\gamma$ be the open cover of balls of radius $\gamma$.
   125 Choose a metric on $X$, and let $\cU_\gamma$ be the open cover of $X$ by balls of radius $\gamma$.
   126 By Lemma \ref{extension_lemma} we can restrict our attention to $k$-parameter families 
   126 By Lemma \ref{extension_lemma} we can restrict our attention to $k$-parameter families 
   127 $p$ of homeomorphisms such that $\supp(p)$ is contained in the union of $k$ $\gamma$-balls.
   127 $p$ of homeomorphisms such that $\supp(p)$ is contained in the union of $k$ $\gamma$-balls.
   128 For fixed blob diagram $b$ and fixed $k$, it's not hard to show that for $\gamma$ small enough
   128 For fixed blob diagram $b$ and fixed $k$, it's not hard to show that for $\gamma$ small enough
   129 $p\ot b$ must be localizable.
   129 $p\ot b$ must be localizable.
   130 On the other hand, for fixed $k$ and $\gamma$ there exist $p$ and $b$ such that $p\ot b$ is not localizable,
   130 On the other hand, for fixed $k$ and $\gamma$ there exist $p$ and $b$ such that $p\ot b$ is not localizable,
   151 
   151 
   152 \begin{proof}[Proof of Proposition \ref{CHprop}.]
   152 \begin{proof}[Proof of Proposition \ref{CHprop}.]
   153 We'll use the notation $|b| = \supp(b)$ and $|p| = \supp(p)$.
   153 We'll use the notation $|b| = \supp(b)$ and $|p| = \supp(p)$.
   154 
   154 
   155 Choose a metric on $X$.
   155 Choose a metric on $X$.
   156 Choose a monotone decreasing sequence of positive real numbers $\ep_i$ converging monotonically to zero
   156 Choose a monotone decreasing sequence of positive real numbers $\ep_i$ converging to zero
   157 (e.g.\ $\ep_i = 2^{-i}$).
   157 (e.g.\ $\ep_i = 2^{-i}$).
   158 Choose another sequence of positive real numbers $\delta_i$ such that $\delta_i/\ep_i$
   158 Choose another sequence of positive real numbers $\delta_i$ such that $\delta_i/\ep_i$
   159 converges monotonically to zero (e.g.\ $\delta_i = \ep_i^2$).
   159 converges monotonically to zero (e.g.\ $\delta_i = \ep_i^2$).
   160 Let $\phi_l$ be an increasing sequence of positive numbers
   160 Let $\phi_l$ be an increasing sequence of positive numbers
   161 satisfying the inequalities of Lemma \ref{xx2phi} below.
   161 satisfying the inequalities of Lemma \ref{xx2phi} below.
   175 We say $p\ot b$ is in $G_*^{i,m}$ exactly when either (a) $\deg(p) = 0$ or (b)
   175 We say $p\ot b$ is in $G_*^{i,m}$ exactly when either (a) $\deg(p) = 0$ or (b)
   176 there exist codimension-zero submanifolds $V_0,\ldots,V_m \sub X$ such that each $V_j$
   176 there exist codimension-zero submanifolds $V_0,\ldots,V_m \sub X$ such that each $V_j$
   177 is homeomorphic to a disjoint union of balls and
   177 is homeomorphic to a disjoint union of balls and
   178 \[
   178 \[
   179 	N_{i,k}(p\ot b) \subeq V_0 \subeq N_{i,k+1}(p\ot b)
   179 	N_{i,k}(p\ot b) \subeq V_0 \subeq N_{i,k+1}(p\ot b)
   180 			\subeq V_1 \subeq \cdots \subeq V_m \subeq N_{i,k+m+1}(p\ot b) .
   180 			\subeq V_1 \subeq \cdots \subeq V_m \subeq N_{i,k+m+1}(p\ot b) ,
   181 \]
   181 \]
   182 and further $\bd(p\ot b) \in G_*^{i,m}$.
   182 and further $\bd(p\ot b) \in G_*^{i,m}$.
   183 We also require that $b$ is splitable (transverse) along the boundary of each $V_l$.
   183 We also require that $b$ is splitable (transverse) along the boundary of each $V_l$.
   184 
   184 
   185 Note that $G_*^{i,m+1} \subeq G_*^{i,m}$.
   185 Note that $G_*^{i,m+1} \subeq G_*^{i,m}$.
   343 
   343 
   344 
   344 
   345 \begin{proof}
   345 \begin{proof}
   346 
   346 
   347 There exists $\lambda > 0$ such that for every  subset $c$ of the blobs of $b$ $\Nbd_u(c)$ is homeomorphic to $|c|$ for all $u < \lambda$ .
   347 There exists $\lambda > 0$ such that for every  subset $c$ of the blobs of $b$ $\Nbd_u(c)$ is homeomorphic to $|c|$ for all $u < \lambda$ .
   348 (Here we are using the fact that the blobs are piecewise-linear and thatthat $\bd c$ is collared.)
   348 (Here we are using the fact that the blobs are 
       
   349 piecewise smooth or piecewise-linear and that $\bd c$ is collared.)
   349 We need to consider all such $c$ because all generators appearing in
   350 We need to consider all such $c$ because all generators appearing in
   350 iterated boundaries of $p\ot b$ must be in $G_*^{i,m}$.)
   351 iterated boundaries of $p\ot b$ must be in $G_*^{i,m}$.)
   351 
   352 
   352 Let $r = \deg(b)$ and 
   353 Let $r = \deg(b)$ and 
   353 \[
   354 \[