text/evmap.tex
changeset 248 9fc815360797
parent 247 f090fd0a12cd
child 249 daf58017eec5
equal deleted inserted replaced
247:f090fd0a12cd 248:9fc815360797
   235 near $\bd V$, the expressions $p(V) \sub X$ and $p(X\setmin V) \sub X$ are
   235 near $\bd V$, the expressions $p(V) \sub X$ and $p(X\setmin V) \sub X$ are
   236 unambiguous.)
   236 unambiguous.)
   237 We have $\deg(p'') = 0$ and, inductively, $f'' = p''(b'')$.
   237 We have $\deg(p'') = 0$ and, inductively, $f'' = p''(b'')$.
   238 %We also have that $\deg(b'') = 0 = \deg(p'')$.
   238 %We also have that $\deg(b'') = 0 = \deg(p'')$.
   239 Choose $x' \in \bc_*(p(V))$ such that $\bd x' = f'$.
   239 Choose $x' \in \bc_*(p(V))$ such that $\bd x' = f'$.
   240 This is possible by \ref{bcontract}, \ref{disjunion} and \nn{property 2 of local relations (isotopy)}.
   240 This is possible by \ref{bcontract}, \ref{disjunion} and the fact that isotopic fields
       
   241 differ by a local relation \nn{give reference?}.
   241 Finally, define
   242 Finally, define
   242 \[
   243 \[
   243 	e(p\ot b) \deq x' \bullet p''(b'') .
   244 	e(p\ot b) \deq x' \bullet p''(b'') .
   244 \]
   245 \]
   245 
   246 
   335 we have $g_j(p)\ot b \in G_*^{i,m}$.
   336 we have $g_j(p)\ot b \in G_*^{i,m}$.
   336 \end{lemma}
   337 \end{lemma}
   337 
   338 
   338 \begin{proof}
   339 \begin{proof}
   339 Let $c$ be a subset of the blobs of $b$.
   340 Let $c$ be a subset of the blobs of $b$.
   340 There exists $l > 0$ such that $\Nbd_u(c)$ is homeomorphic to $|c|$ for all $u < l$ 
   341 There exists $\lambda > 0$ such that $\Nbd_u(c)$ is homeomorphic to $|c|$ for all $u < \lambda$ 
   341 and all such $c$.
   342 and all such $c$.
   342 (Here we are using a piecewise smoothness assumption for $\bd c$, and also
   343 (Here we are using a piecewise smoothness assumption for $\bd c$, and also
   343 the fact that $\bd c$ is collared.
   344 the fact that $\bd c$ is collared.
   344 We need to consider all such $c$ because all generators appearing in
   345 We need to consider all such $c$ because all generators appearing in
   345 iterated boundaries of $p\ot b$ must be in $G_*^{i,m}$.)
   346 iterated boundaries of $p\ot b$ must be in $G_*^{i,m}$.)
   349 	t = r+n+m+1 = \deg(p\ot b) + m + 1.
   350 	t = r+n+m+1 = \deg(p\ot b) + m + 1.
   350 \]
   351 \]
   351 
   352 
   352 Choose $k = k_{bmn}$ such that
   353 Choose $k = k_{bmn}$ such that
   353 \[
   354 \[
   354 	t\ep_k < l
   355 	t\ep_k < \lambda
   355 \]
   356 \]
   356 and
   357 and
   357 \[
   358 \[
   358 	n\cdot (2 (\phi_t + 1) \delta_k) < \ep_k .
   359 	n\cdot (2 (\phi_t + 1) \delta_k) < \ep_k .
   359 \]
   360 \]
   373 is homeomorphic to a disjoint union of balls and
   374 is homeomorphic to a disjoint union of balls and
   374 \[
   375 \[
   375 	N_{i,n}(q\ot b) \subeq V_0 \subeq N_{i,n+1}(q\ot b)
   376 	N_{i,n}(q\ot b) \subeq V_0 \subeq N_{i,n+1}(q\ot b)
   376 			\subeq V_1 \subeq \cdots \subeq V_m \subeq N_{i,t}(q\ot b) .
   377 			\subeq V_1 \subeq \cdots \subeq V_m \subeq N_{i,t}(q\ot b) .
   377 \]
   378 \]
       
   379 Recall that
       
   380 \[
       
   381 	N_{i,a}(q\ot b) \deq \Nbd_{a\ep_i}(|b|) \cup \Nbd_{\phi_a\delta_i}(|q|).
       
   382 \]
   378 By repeated applications of Lemma \ref{xx2phi} we can find neighborhoods $U_0,\ldots,U_m$
   383 By repeated applications of Lemma \ref{xx2phi} we can find neighborhoods $U_0,\ldots,U_m$
   379 of $|q|$, each homeomorphic to a disjoint union of balls, with
   384 of $|q|$, each homeomorphic to a disjoint union of balls, with
   380 \[
   385 \[
   381 	\Nbd_{\phi_{n+l} \delta_i}(|q|) \subeq U_l \subeq \Nbd_{\phi_{n+l+1} \delta_i}(|q|) .
   386 	\Nbd_{\phi_{n+l} \delta_i}(|q|) \subeq U_l \subeq \Nbd_{\phi_{n+l+1} \delta_i}(|q|) .
   382 \]
   387 \]
   383 The inequalities above \nn{give ref} guarantee that we can find $u_l$ with 
   388 The inequalities above guarantee that 
       
   389 for each $0\le l\le m$ we can find $u_l$ with 
   384 \[
   390 \[
   385 	(n+l)\ep_i \le u_l \le (n+l+1)\ep_i
   391 	(n+l)\ep_i \le u_l \le (n+l+1)\ep_i
   386 \]
   392 \]
   387 such that each component of $U_l$ is either disjoint from $\Nbd_{u_l}(|b|)$ or contained in 
   393 such that each component of $U_l$ is either disjoint from $\Nbd_{u_l}(|b|)$ or contained in 
   388 $\Nbd_{u_l}(|b|)$.
   394 $\Nbd_{u_l}(|b|)$.
   450 Let $S \sub M$ be contained in a union (not necessarily disjoint)
   456 Let $S \sub M$ be contained in a union (not necessarily disjoint)
   451 of $k$ metric balls of radius $r$.
   457 of $k$ metric balls of radius $r$.
   452 Let $\phi_1, \phi_2, \ldots$ be an increasing sequence of real numbers satisfying
   458 Let $\phi_1, \phi_2, \ldots$ be an increasing sequence of real numbers satisfying
   453 $\phi_1 \ge 2$ and $\phi_{i+1} \ge \phi_i(2\phi_i + 2) + \phi_i$.
   459 $\phi_1 \ge 2$ and $\phi_{i+1} \ge \phi_i(2\phi_i + 2) + \phi_i$.
   454 For convenience, let $\phi_0 = 0$.
   460 For convenience, let $\phi_0 = 0$.
   455 Assume also that $\phi_k r \le \rho(M)$.
   461 Assume also that $\phi_k r \le \rho(M)$,
       
   462 where $\rho(M)$ is as in Lemma \ref{xxzz11}.
   456 Then there exists a neighborhood $U$ of $S$,
   463 Then there exists a neighborhood $U$ of $S$,
   457 homeomorphic to a disjoint union of balls, such that
   464 homeomorphic to a disjoint union of balls, such that
   458 \[
   465 \[
   459 	\Nbd_{\phi_{k-1} r}(S) \subeq U \subeq \Nbd_{\phi_k r}(S) .
   466 	\Nbd_{\phi_{k-1} r}(S) \subeq U \subeq \Nbd_{\phi_k r}(S) .
   460 \]
   467 \]