diff -r 85d7b17c636c -r 5f22b4501e5f text/ncat.tex --- a/text/ncat.tex Thu Jan 06 23:10:55 2011 -0800 +++ b/text/ncat.tex Fri Jan 07 09:08:15 2011 -0800 @@ -671,6 +671,31 @@ Conversely, given a topological $n$-category we can construct a system of fields via a colimit construction; see \S \ref{ss:ncat_fields} below. +In the $n$-category axioms above we have intermingled data and properties for expository reasons. +Here's a summary of the definition which segregates the data from the properties. + +An $n$-category consists of the following data: +\begin{itemize} +\item Functors $\cC_k$ from $k$-balls to sets, $0\le k\le n$ (Axiom \ref{axiom:morphisms}) +\item Boundary natural transformations $\cC_k \to \cl{\cC}_{k-1} \circ \bd$ (Axiom \ref{nca-boundary}) +\item Composition/gluing maps $\gl_Y : \cC(B_1)_E \times_{\cC(Y)} \cC(B_2)_E \to \cC(B_1\cup_Y B_2)_E$ (Axiom \ref{axiom:composition}) +\item Product/identity maps $\pi^*:\cC(X)\to \cC(E)$ for each pinched product $\pi:E\to X$ (Axiom \ref{axiom:product}) +\item If enriching in an auxiliary category, additional structure on $\cC_n(X; c)$ +\item In the $A_\infty$ case, an action of $C_*(\Homeo_\bd(X))$, and similarly for families of collar maps (Axiom \ref{axiom:families}) +\end{itemize} +The above data must satisfy the following conditions: +\begin{itemize} +\item The gluing maps are compatible with actions of homeomorphisms and boundary +restrictions (Axiom \ref{axiom:composition}). +\item For $k