# HG changeset patch # User kevin@6e1638ff-ae45-0410-89bd-df963105f760 # Date 1225117920 0 # Node ID dd9487823529863aedde0573a1c1b18fb03780a8 # Parent 75c9b874dea749df64f4ffa7fa079779b2b2d521 ... diff -r 75c9b874dea7 -r dd9487823529 blob1.tex --- a/blob1.tex Sun Oct 26 22:20:59 2008 +0000 +++ b/blob1.tex Mon Oct 27 14:32:00 2008 +0000 @@ -1497,7 +1497,7 @@ \end{proof} -\begin{prop} +\begin{prop} \label{ktcdprop} The above maps are compatible with the evaluation map actions of $C_*(\Diff(M))$. \end{prop} @@ -1514,12 +1514,26 @@ \nn{probably should put a more precise statement about cyclic homology and $S^1$ actions in the Hochschild section} Let us check this directly. +According to \nn{Loday, 3.2.2}, $HH_i(k[t]) \cong k[t]$ for $i=0,1$ and is zero for $i\ge 2$. +\nn{say something about $t$-degree? is this in [Loday]?} + We can define a flow on $\Sigma^j(S^1)$ by having the points repel each other. The fixed points of this flow are the equally spaced configurations. -This defines a map from $\Sigma^j(S^1)$ to $S^1/j$ ($S^1$ modulo a $2\pi/j$ rotation.). +This defines a map from $\Sigma^j(S^1)$ to $S^1/j$ ($S^1$ modulo a $2\pi/j$ rotation). The fiber of this map is $\Delta^{j-1}$, the $(j-1)$-simplex, and the holonomy of the $\Delta^{j-1}$ bundle -over $S^1$ is the cyclic permutation of its $j$ vertices. +over $S^1/j$ is induced by the cyclic permutation of its $j$ vertices. + +In particular, $\Sigma^j(S^1)$ is homotopy equivalent to a circle for $j>0$, and +of course $\Sigma^0(S^1)$ is a point. +Thus the singular homology $H_i(\Sigma^\infty(S^1))$ has infinitely many generators for $i=0,1$ +and is zero for $i\ge 2$. +\nn{say something about $t$-degrees also matching up?} + +By xxxx and \ref{ktcdprop}, +the cyclic homology of $k[t]$ is the $S^1$-equivariant homology of $\Sigma^\infty(S^1)$. +Up to homotopy, $S^1$ acts by $j$-fold rotation on $\Sigma^j(S^1) \simeq S^1/j$. +If $k = \z$, we then have