text/basic_properties.tex
changeset 403 ef36cdefb130
parent 342 1d76e832d32f
child 409 291f82fb79b5
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402:853376c08d76 403:ef36cdefb130
    85 We will use the method of acyclic models.
    85 We will use the method of acyclic models.
    86 Let $b$ be a blob diagram of $L_*$, let $S\sub X$ be the support of $b$, and let
    86 Let $b$ be a blob diagram of $L_*$, let $S\sub X$ be the support of $b$, and let
    87 $r$ be the restriction of $b$ to $X\setminus S$.
    87 $r$ be the restriction of $b$ to $X\setminus S$.
    88 Note that $S$ is a disjoint union of balls.
    88 Note that $S$ is a disjoint union of balls.
    89 Assign to $b$ the acyclic (in positive degrees) subcomplex $T(b) \deq r\bullet\bc_*(S)$.
    89 Assign to $b$ the acyclic (in positive degrees) subcomplex $T(b) \deq r\bullet\bc_*(S)$.
    90 note that if a diagram $b'$ is part of $\bd b$ then $T(B') \sub T(b)$.
    90 Note that if a diagram $b'$ is part of $\bd b$ then $T(B') \sub T(b)$.
    91 Both $f$ and the identity are compatible with $T$ (in the sense of acyclic models), 
    91 Both $f$ and the identity are compatible with $T$ (in the sense of acyclic models), 
    92 so $f$ and the identity map are homotopic.
    92 so $f$ and the identity map are homotopic. \nn{We should actually have a section with a definition of `compatible' and this statement as a lemma}
    93 \end{proof}
    93 \end{proof}
    94 
    94 
    95 For the next proposition we will temporarily restore $n$-manifold boundary
    95 For the next proposition we will temporarily restore $n$-manifold boundary
    96 conditions to the notation.
    96 conditions to the notation.
    97 
    97