# HG changeset patch # User Kevin Walker # Date 1273705040 25200 # Node ID 3278eafef6683cc5eb69afd0643342bf494d352e # Parent 1c408505c9f5f3f69570fe3ab9a9ae3a26c69f12 done for the moment with module morphism stuff diff -r 1c408505c9f5 -r 3278eafef668 diagrams/pdf/tempkw/left-marked-antirefinements.pdf Binary file diagrams/pdf/tempkw/left-marked-antirefinements.pdf has changed diff -r 1c408505c9f5 -r 3278eafef668 text/ncat.tex --- a/text/ncat.tex Mon May 10 19:34:59 2010 -0700 +++ b/text/ncat.tex Wed May 12 15:57:20 2010 -0700 @@ -744,7 +744,7 @@ \subsection{Modules} -Next we define topological and $A_\infty$ $n$-category modules. +Next we define plain and $A_\infty$ $n$-category modules. The definition will be very similar to that of $n$-categories, but with $k$-balls replaced by {\it marked $k$-balls,} defined below. \nn{** need to make sure all revisions of $n$-cat def are also made to module def.} @@ -755,6 +755,8 @@ Such a $W$ gives rise to a module for the $n$-category associated to $\bd W$. This will be explained in more detail as we present the axioms. +\nn{should also develop $\pi_{\le n}(T, S)$ as a module for $\pi_{\le n}(T)$, where $S\sub T$.} + Throughout, we fix an $n$-category $\cC$. For all but one axiom, it doesn't matter whether $\cC$ is a topological $n$-category or an $A_\infty$ $n$-category. We state the final axiom, on actions of homeomorphisms, differently in the two cases. Define a {\it marked $k$-ball} to be a pair $(B, N)$ homeomorphic to the pair @@ -1096,7 +1098,7 @@ In order to state and prove our version of the higher dimensional Deligne conjecture (Section \ref{sec:deligne}), we need to define morphisms of $A_\infty$ 1-cat modules and establish -some elementary properties of these. +some of their elementary properties. To motivate the definitions which follow, consider algebras $A$ and $B$, right/bi/left modules $X_B$, $_BY_A$ and $Z_A$, and the familiar adjunction @@ -1116,7 +1118,7 @@ (\cM_\cC\ot {_\cC\cN})^* \cong \hom_\cC(\cM_\cC \to (_\cC\cN)^*) . \] -In the next few paragraphs define the things appearing in the above equation: +In the next few paragraphs we define the things appearing in the above equation: $\cM_\cC\ot {_\cC\cN}$, $(\cM_\cC\ot {_\cC\cN})^*$, $(_\cC\cN)^*$ and finally $\hom_\cC$. @@ -1179,6 +1181,7 @@ where $({_\cC\cN}(J\setmin K))^*$ denotes the (linear) dual of the chain complex associated to the right-marked interval $J\setmin K$. This extends to a functor from all left-marked intervals (not just those contained in $J$). +\nn{need to say more here; not obvious how homeomorphisms act} It's easy to verify the remaining module axioms. Now we reinterpret $(\cM_\cC\ot {_\cC\cN})^*$ @@ -1201,7 +1204,10 @@ omitted. More specifically, $D\to D'$ is an antirefinement if $D'$ is obtained from $D$ by gluing subintervals together and/or omitting some of the rightmost subintervals. -(See Figure xxxx.) +(See Figure \ref{fig:lmar}.) +\begin{figure}[t]\begin{equation*} +\mathfig{.6}{tempkw/left-marked-antirefinements} +\end{equation*}\caption{Antirefinements of left-marked intervals}\label{fig:lmar}\end{figure} Now we define the chain complex $\hom_\cC(\cX_\cC \to \cY_\cC)$. The underlying vector space is @@ -1243,6 +1249,47 @@ $g((\bd \olD)\ot -)$ (where the $g((\bd_0 \olD)\ot -)$ part of $g((\bd \olD)\ot -)$ should be interpreted as above). +Define a {\it naive morphism} +\nn{should consider other names for this} +of modules to be a collection of {\it chain} maps +\[ + h_K : \cX(K)\to \cY(K) +\] +for each left-marked interval $K$. +These are required to commute with gluing; +for each subdivision $K = I_1\cup\cdots\cup I_q$ the following diagram commutes: +\[ \xymatrix{ + \cX(I_1)\ot\cC(I_2)\ot\cdots\ot\cC(I_q) \ar[r]^{h_{I_0}\ot \id} + \ar[d]_{\gl} & \cY(I_1)\ot\cC(I_2)\ot\cdots\ot\cC(I_q) + \ar[d]^{\gl} \\ + \cX(K) \ar[r]^{h_{K}} & \cY(K) +} \] +Given such an $h$ we can construct a non-naive morphism $g$, with $\bd g = 0$, as follows. +Define $g(\olD\ot - ) = 0$ if the length/degree of $\olD$ is greater than 0. +If $\olD$ consists of the single subdivision $K = I_0\cup\cdots\cup I_q$ then define +\[ + g(\olD\ot x\ot \cbar) \deq h_K(\gl(x\ot\cbar)) . +\] +Trivially, we have $(\bd g)(\olD\ot x \ot \cbar) = 0$ if $\deg(\olD) > 1$. +If $\deg(\olD) = 1$, $(\bd g) = 0$ is equivalent to the fact that $h$ commutes with gluing. +If $\deg(\olD) = 0$, $(\bd g) = 0$ is equivalent to the fact +that each $h_K$ is a chain map. + +\medskip + +Given $_\cC\cZ$ and $g: \cX_\cC \to \cY_\cC$ with $\bd g = 0$ as above, we next define a chain map +\[ + g\ot\id : \cX_\cC \ot {}_\cC\cZ \to \cY_\cC \ot {}_\cC\cZ . +\] +\nn{this is fairly straightforward, but the details are messy enough that I'm inclined +to postpone writing it up, in the hopes that I'll think of a better way to organize things.} + + + + +\medskip + + \nn{do we need to say anything about composing morphisms of modules?} \nn{should we define functors between $n$-cats in a similar way?}