# HG changeset patch # User Scott Morrison # Date 1290379674 28800 # Node ID 0175e0b7e13198f0ee3f4e612c185e1d4a0b5fee # Parent a356cb8a83ca2c8cbde171b03f24a5e504c0039b minor diff -r a356cb8a83ca -r 0175e0b7e131 pnas/pnas.tex --- a/pnas/pnas.tex Thu Nov 18 12:06:17 2010 -0800 +++ b/pnas/pnas.tex Sun Nov 21 14:47:54 2010 -0800 @@ -96,7 +96,7 @@ %% For titles, only capitalize the first letter %% \title{Almost sharp fronts for the surface quasi-geostrophic equation} -\title{Higher categories, colimits and the blob complex} +\title{Higher categories, colimits, and the blob complex} %% Enter authors via the \author command. @@ -171,7 +171,7 @@ \dropcap{T}he aim of this paper is to describe a derived category analogue of topological quantum field theories. For our purposes, an $n{+}1$-dimensional TQFT is a locally defined system of -invariants of manifolds of dimensions 0 through $n+1$. In particular, +invariants of manifolds of dimensions 0 through $n{+}1$. In particular, 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 $A(\bd Y)$. @@ -239,7 +239,7 @@ Of course, there are currently many interesting alternative notions of $n$-category and of TQFT. We note that our $n$-categories are both more and less general than the ``fully dualizable" ones which play a prominent role in \cite{0905.0465}. -They are more general in that we make no duality assumptions in the top dimension $n+1$. +They are more general in that we make no duality assumptions in the top dimension $n{+}1$. They are less general in that we impose stronger duality requirements in dimensions 0 through $n$. Thus our $n$-categories correspond to $(n{+}\epsilon)$-dimensional unoriented or oriented TQFTs, while Lurie's (fully dualizable) $n$-categories correspond to $(n{+}1)$-dimensional framed TQFTs. @@ -546,7 +546,7 @@ An $n$-category $\cC$ determines a functor $\psi_{\cC;W}$ from $\cell(W)$ to the category of sets (possibly with additional structure if $k=n$). -Each $k$-ball $X$ of a decomposition $y$ of $W$ has its boundary decomposed into $k{-}1$-balls, +Each $k$-ball $X$ of a decomposition $y$ of $W$ has its boundary decomposed into $k{-}1$-manifolds, and there is a subset $\cC(X)\spl \subset \cC(X)$ of morphisms whose boundaries are splittable along this decomposition. @@ -557,8 +557,8 @@ %\label{eq:psi-C} \psi_{\cC;W}(x) \subset \prod_a \cC(X_a)\spl \end{equation*} -where the restrictions to the various pieces of shared boundaries amongst the cells -$X_a$ all agree (this is a fibered product of all the labels of $k$-cells over the labels of $k-1$-cells). +where the restrictions to the various pieces of shared boundaries amongst the balls +$X_a$ all agree (this is a fibered product of all the labels of $k$-balls over the labels of $k-1$-manifolds). When $k=n$, the `subset' and `product' in the above formula should be interpreted in the appropriate enriching category. If $x$ is a refinement of $y$, the map $\psi_{\cC;W}(x) \to \psi_{\cC;W}(y)$ is given by the composition maps of $\cC$.