# HG changeset patch # User Scott Morrison # Date 1304727651 25200 # Node ID abeb2bd9233ed6b02caaf07422ccaa3fc815b4db # Parent cfd1521a098687db79d935931341e168343fd4a6# Parent d2611b2744bb18bdda420bd171b54ae27814e1b3 Automated merge with https://tqft.net/hg/blob/ diff -r d2611b2744bb -r abeb2bd9233e pnas/pnas.tex --- a/pnas/pnas.tex Fri May 06 15:32:55 2011 -0700 +++ b/pnas/pnas.tex Fri May 06 17:20:51 2011 -0700 @@ -392,7 +392,7 @@ the TQFT invariant $A(Y)$ of a closed $k$-manifold $Y$ is a linear $(n{-}k)$-category. If $Y$ has boundary then $A(Y)$ is a collection of $(n{-}k)$-categories which afford a representation of the $(n{-}k{+}1)$-category $A(\bd Y)$. -(See \cite{1009.5025} and \cite{kw:tqft}; +(See \cite{1009.5025} and references therein; for a more homotopy-theoretic point of view see \cite{0905.0465}.) We now comment on some particular values of $k$ above. diff -r d2611b2744bb -r abeb2bd9233e text/ncat.tex --- a/text/ncat.tex Fri May 06 15:32:55 2011 -0700 +++ b/text/ncat.tex Fri May 06 17:20:51 2011 -0700 @@ -124,10 +124,13 @@ \end{lem} We postpone the proof of this result until after we've actually given all the axioms. -Note that defining this functor for some $k$ only requires the data described in Axiom \ref{axiom:morphisms} at level $k$, -along with the data described in the other axioms at lower levels. +Note that defining this functor for fixed $k$ only requires the data described in Axiom \ref{axiom:morphisms} at level $k$, +along with the data described in the other axioms for smaller values of $k$. -%In fact, the functors for spheres are entirely determined by the functors for balls and the subsequent axioms. (In particular, $\cC(S^k)$ is the colimit of $\cC$ applied to decompositions of $S^k$ into balls.) However, it is easiest to think of it as additional data at this point. +Of course, Lemma \ref{lem:spheres}, as stated, is satisfied by the trivial functor. +What we really mean is that there exists a functor which interacts with the other data of $\cC$ as specified +in the axioms below. + \begin{axiom}[Boundaries]\label{nca-boundary} For each $k$-ball $X$, we have a map of sets $\bd: \cC_k(X)\to \cl{\cC}_{k-1}(\bd X)$. @@ -397,8 +400,12 @@ $$ \caption{Examples of pinched products}\label{pinched_prods} \end{figure} -(The need for a strengthened version will become apparent in Appendix \ref{sec:comparing-defs} -where we construct a traditional category from a disk-like category.) +The need for a strengthened version will become apparent in Appendix \ref{sec:comparing-defs} +where we construct a traditional category from a disk-like category. +For example, ``half-pinched" products of 1-balls are used to construct weak identities for 1-morphisms +in 2-categories. +We also need fully-pinched products to define collar maps below (see Figure \ref{glue-collar}). + Define a {\it pinched product} to be a map \[ \pi: E\to X