--- a/text/ncat.tex Tue Jun 01 21:44:09 2010 -0700
+++ b/text/ncat.tex Tue Jun 01 23:07:42 2010 -0700
@@ -74,7 +74,7 @@
We will concentrate on the case of PL unoriented manifolds.
(The ambitious reader may want to keep in mind two other classes of balls.
-The first is balls equipped with a map to some other space $Y$. \todo{cite something of Teichner's?}
+The first is balls equipped with a map to some other space $Y$ (c.f. \cite{MR2079378}).
This will be used below to describe the blob complex of a fiber bundle with
base space $Y$.
The second is balls equipped with a section of the the tangent bundle, or the frame
@@ -86,7 +86,7 @@
of morphisms).
The 0-sphere is unusual among spheres in that it is disconnected.
Correspondingly, for 1-morphisms it makes sense to distinguish between domain and range.
-(Actually, this is only true in the oriented case, with 1-morphsims parameterized
+(Actually, this is only true in the oriented case, with 1-morphisms parameterized
by oriented 1-balls.)
For $k>1$ and in the presence of strong duality the division into domain and range makes less sense. For example, in a pivotal tensor category, there are natural isomorphisms $\Hom{}{A}{B \tensor C} \isoto \Hom{}{B^* \tensor A}{C}$, etc. (sometimes called ``Frobenius reciprocity''), which canonically identify all the morphism spaces which have the same boundary. We prefer to not make the distinction in the first place.
@@ -123,7 +123,7 @@
Most of the examples of $n$-categories we are interested in are enriched in the following sense.
The various sets of $n$-morphisms $\cC(X; c)$, for all $n$-balls $X$ and
-all $c\in \cC(\bd X)$, have the structure of an object in some auxiliary category
+all $c\in \cC(\bd X)$, have the structure of an object in some auxiliary symmetric monoidal category
(e.g.\ vector spaces, or modules over some ring, or chain complexes),
and all the structure maps of the $n$-category should be compatible with the auxiliary
category structure.
@@ -142,7 +142,7 @@
equipped with an orientation of its once-stabilized tangent bundle.
Similarly, in dimension $n-k$ we would have manifolds equipped with an orientation of
their $k$ times stabilized tangent bundles.
-(cf. [Stolz and Teichner].)
+(cf. \cite{MR2079378}.)
Probably should also have a framing of the stabilized dimensions in order to indicate which
side the bounded manifold is on.
For the moment just stick with unoriented manifolds.}
@@ -780,23 +780,6 @@
(actions of homeomorphisms);
define $k$-cat $\cC(\cdot\times W)$}
-\nn{need to revise stuff below, since we no longer have the sphere axiom}
-
-Recall that Axiom \ref{axiom:spheres} for an $n$-category provided functors $\cC$ from $k$-spheres to sets for $0 \leq k < n$. We claim now that these functors automatically agree with the colimits we have associated to spheres in this section. \todo{} \todo{In fact, we probably should do this for balls as well!} For the remainder of this section we will write $\underrightarrow{\cC}(W)$ for the colimit associated to an arbitary manifold $W$, to distinguish it, in the case that $W$ is a ball or a sphere, from $\cC(W)$, which is part of the definition of the $n$-category. After the next three lemmas, there will be no further need for this notational distinction.
-
-\begin{lem}
-For a $k$-ball or $k$-sphere $W$, with $0\leq k < n$, $$\underrightarrow{\cC}(W) = \cC(W).$$
-\end{lem}
-
-\begin{lem}
-For a topological $n$-category $\cC$, and an $n$-ball $B$, $$\underrightarrow{\cC}(B) = \cC(B).$$
-\end{lem}
-
-\begin{lem}
-For an $A_\infty$ $n$-category $\cC$, and an $n$-ball $B$, $$\underrightarrow{\cC}(B) \quism \cC(B).$$
-\end{lem}
-
-
\subsection{Modules}
Next we define plain and $A_\infty$ $n$-category modules.