# HG changeset patch # User Kevin Walker # Date 1323374803 28800 # Node ID 082bfb8f6325b2fe3bbaf4c6cb3a38b3127d5a6b # Parent 6cfc2dc6ec6edc56ecc36d7f1125e1b5a660f378 minor edits in section 3.1 diff -r 6cfc2dc6ec6e -r 082bfb8f6325 blob to-do --- a/blob to-do Thu Dec 08 09:45:16 2011 -0800 +++ b/blob to-do Thu Dec 08 12:06:43 2011 -0800 @@ -1,6 +1,10 @@ ====== big ====== +* add "homeomorphism" spiel befure the first use of "homeomorphism in the intro +* maybe also additional homeo warnings in other sections + + ====== minor/optional ====== [probably NO] * consider proving the gluing formula for higher codimension manifolds with @@ -13,7 +17,6 @@ * figures (** 13 "combining two balls" is lame) (but maybe leave it as is -- KW) -** figures for email thread with Mike Schulman?? * better discussion of systems of fields from disk-like n-cats diff -r 6cfc2dc6ec6e -r 082bfb8f6325 text/blobdef.tex --- a/text/blobdef.tex Thu Dec 08 09:45:16 2011 -0800 +++ b/text/blobdef.tex Thu Dec 08 12:06:43 2011 -0800 @@ -80,7 +80,7 @@ Next, we want the vector space $\bc_2(X)$ to capture ``the space of all relations (redundancies, syzygies) among the local relations encoded in $\bc_1(X)$''. -A $2$-blob diagram, comes in one of two types, disjoint and nested. +A $2$-blob diagram comes in one of two types, disjoint and nested. A disjoint 2-blob diagram consists of \begin{itemize} \item A pair of closed balls (blobs) $B_1, B_2 \sub X$ with disjoint interiors. @@ -190,7 +190,7 @@ We say that a field $a\in \cF(X)$ is splittable along the decomposition if $a$ is the image under gluing and disjoint union of fields $a_i \in \cF(M_0^i)$, $0\le i\le k$. -Note that if $a$ is splittable in the sense then it makes sense to talk about the restriction of $a$ of any +Note that if $a$ is splittable in this sense then it makes sense to talk about the restriction of $a$ to any component $M'_j$ of any $M_j$ of the decomposition. In the example above, note that @@ -209,9 +209,10 @@ \begin{defn} \label{defn:configuration} A configuration of $k$ blobs in $X$ is an ordered collection of $k$ subsets $\{B_1, \ldots, B_k\}$ -of $X$ such that there exists a gluing decomposition $M_0 \to \cdots \to M_m = X$ of $X$ and +of $X$ such that there exists a gluing decomposition $M_0 \to \cdots \to M_m = X$ of $X$ +with the property that for each subset $B_i$ there is some $0 \leq l \leq m$ and some connected component $M_l'$ of -$M_l$ which is a ball, so $B_i$ is the image of $M_l'$ in $X$. +$M_l$ which is a ball, such that $B_i$ is the image of $M_l'$ in $X$. We say that such a gluing decomposition is \emph{compatible} with the configuration. A blob $B_i$ is a twig blob if no other blob $B_j$ is a strict subset of it. @@ -229,10 +230,10 @@ if the boundaries of all the blobs cut $X$ into pieces which are all manifolds, we can just take $M_0$ to be these pieces, and $M_1 = X$. -In the informal description above, in the definition of a $k$-blob diagram we asked for any +In the initial informal definition of a $k$-blob diagram above, we allowed any collection of $k$ balls which were pairwise disjoint or nested. -We now further insist that the balls are a configuration in the sense of Definition \ref{defn:configuration}. -Also, we asked for a local relation on each twig blob, and a field on the complement of the twig blobs; +We now further require that the balls are a configuration in the sense of Definition \ref{defn:configuration}. +We also specified a local relation on each twig blob, and a field on the complement of the twig blobs; this is unsatisfactory because that complement need not be a manifold. Thus, the official definitions are \begin{defn} \label{defn:blob-diagram} @@ -251,7 +252,7 @@ \begin{figure}[t]\begin{equation*} \mathfig{.7}{definition/k-blobs} \end{equation*}\caption{A $k$-blob diagram.}\label{blobkdiagram}\end{figure} -and + \begin{defn} \label{defn:blobs} The $k$-th vector space $\bc_k(X)$ of the \emph{blob complex} of $X$ is the direct sum over all @@ -287,7 +288,8 @@ \item $p(a \du b) = p(a) \times p(b)$, where $a \du b$ denotes the distant (non-overlapping) union of two blob diagrams (equivalently, join two trees at the roots); and \item $p(\bar{b}) = \kone(p(b))$, where $\bar{b}$ is obtained from $b$ by adding an outer blob which -encloses all the others (equivalently, add a new edge to the root, with the new vertex becoming the root). +encloses all the others (equivalently, add a new edge to the root, with the new vertex becoming the root +of the new tree). \end{itemize} For example, a diagram of $k$ strictly nested blobs corresponds to a $k$-simplex, while a diagram of $k$ disjoint blobs corresponds to a $k$-cube.