talks/20091108-Riverside/riverside1.tex
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    99 \section{Definition}
    99 \section{Definition}
   100 \begin{frame}{Fields and pasting diagrams}
   100 \begin{frame}{Fields and pasting diagrams}
   101 \begin{block}{Pasting diagrams}
   101 \begin{block}{Pasting diagrams}
   102 Fix an $n$-category with strong duality $\cC$. A \emph{field} on $\cM$ is a pasting diagram drawn on $\cM$, with cells labelled by morphisms from $\cC$.
   102 Fix an $n$-category with strong duality $\cC$. A \emph{field} on $\cM$ is a pasting diagram drawn on $\cM$, with cells labelled by morphisms from $\cC$.
   103 \end{block}
   103 \end{block}
       
   104 \begin{example}[$\cC = \text{TL}_d$ the Temperley-Lieb category]
       
   105 $$\roundframe{\mathfig{0.35}{definition/example-pasting-diagram}} \in \cF^{\text{TL}_d}\left(T^2\right)$$
       
   106 \end{example}
       
   107 \begin{block}{}
       
   108 Given a pasting diagram on a ball, we can evaluate it to a morphism. We call the kernel the \emph{null fields}.
       
   109 \vspace{-3mm}
       
   110 $$\text{ev}\Bigg(\roundframe{\mathfig{0.12}{definition/evaluation1}} - \frac{1}{d}\roundframe{\mathfig{0.12}{definition/evaluation2}}\Bigg) = 0$$
       
   111 \end{block}
   104 \end{frame}
   112 \end{frame}
   105 
   113 
   106 \begin{frame}{Background: TQFT invariants}
   114 \begin{frame}{Background: TQFT invariants}
   107 \begin{defn}
   115 \begin{defn}
   108 A decapitated $n+1$-dimensional TQFT associates a vector space $\cA(\cM)$ to each $n$-manifold $\cM$.
   116 A decapitated $n+1$-dimensional TQFT associates a vector space $\cA(\cM)$ to each $n$-manifold $\cM$.
   137 $\bc_0(\cM; \cC) = \cF(\cM)$, arbitrary pasting diagrams on $\cM$.
   145 $\bc_0(\cM; \cC) = \cF(\cM)$, arbitrary pasting diagrams on $\cM$.
   138 \end{block}
   146 \end{block}
   139 
   147 
   140 \begin{block}{}
   148 \begin{block}{}
   141 \vspace{-1mm}
   149 \vspace{-1mm}
   142 $$\bc_1(\cM; \cC) = \setcr{(B, u, r)}{\begin{array}{c}\text{$B$ an embedded ball}\\\text{$u \in \cF(B)$ in the kernel}\\ r \in \cF(\cM \setminus B)\end{array}}.$$
   150 $$\bc_1(\cM; \cC) = \Complex\setcr{(B, u, r)}{\begin{array}{c}\text{$B$ an embedded ball}\\\text{$u \in \cF(B)$ in the kernel}\\ r \in \cF(\cM \setminus B)\end{array}}.$$
   143 \end{block}
   151 \end{block}
   144 \vspace{-3.5mm}
   152 \vspace{-3.5mm}
   145 $$\mathfig{.5}{definition/single-blob}$$
   153 $$\mathfig{.5}{definition/single-blob}$$
   146 \vspace{-3mm}
   154 \vspace{-3mm}
   147 \begin{block}{}
   155 \begin{block}{}
   158 $$\bc_2 = \bc_2^{\text{disjoint}} \oplus \bc_2^{\text{nested}}$$
   166 $$\bc_2 = \bc_2^{\text{disjoint}} \oplus \bc_2^{\text{nested}}$$
   159 \end{block}
   167 \end{block}
   160 \begin{block}{}
   168 \begin{block}{}
   161 \vspace{-5mm}
   169 \vspace{-5mm}
   162 \begin{align*}
   170 \begin{align*}
   163 \bc_2^{\text{disjoint}} & =  \setcl{\roundframe{\mathfig{0.5}{definition/disjoint-blobs}}}{\text{ev}_{B_i}(u_i) = 0}
   171 \bc_2^{\text{disjoint}} & =  \Complex\setcl{\roundframe{\mathfig{0.5}{definition/disjoint-blobs}}}{\text{ev}_{B_i}(u_i) = 0}
   164 \end{align*}
   172 \end{align*}
   165 \vspace{-4mm}
   173 \vspace{-4mm}
   166 $$d_2 : (B_1, B_2, u_1, u_2, r) \mapsto (B_2, u_2, r \circ u_1) - (B_1, u_1, r \circ u_2)$$
   174 $$d_2 : (B_1, B_2, u_1, u_2, r) \mapsto (B_2, u_2, r \circ u_1) - (B_1, u_1, r \circ u_2)$$
   167 \end{block}
   175 \end{block}
   168 \begin{block}{}
   176 \begin{block}{}
   169 \vspace{-5mm}
   177 \vspace{-5mm}
   170 \begin{align*}
   178 \begin{align*}
   171 \bc_2^{\text{nested}} & = \setcl{\roundframe{\mathfig{0.5}{definition/nested-blobs}}}{\text{ev}_{B_1}(u)=0}
   179 \bc_2^{\text{nested}} & = \Complex\setcl{\roundframe{\mathfig{0.5}{definition/nested-blobs}}}{\text{ev}_{B_1}(u)=0}
   172 \end{align*}
   180 \end{align*}
   173 \vspace{-4mm}
   181 \vspace{-4mm}
   174 $$d_2 : (B_1, B_2, u, r', r) \mapsto (B_2, u \circ r', r) - (B_1, u, r \circ r')$$
   182 $$d_2 : (B_1, B_2, u, r', r) \mapsto (B_2, u \circ r', r) - (B_1, u, r \circ r')$$
   175 \end{block}
   183 \end{block}
   176 \end{frame}
   184 \end{frame}
   177 
   185 
   178 \begin{frame}{Definition, general case}
   186 \begin{frame}{Definition, general case}
   179 \begin{block}{}
   187 \begin{block}{}
   180 $$\bc_k = \set{\roundframe{\mathfig{0.7}{definition/k-blobs}}}$$
   188 $$\bc_k = \Complex\set{\roundframe{\mathfig{0.7}{definition/k-blobs}}}$$
   181 $k$ blobs, properly nested or disjoint, with ``innermost'' blobs labelled by pasting diagrams that evaluate to zero.
   189 $k$ blobs, properly nested or disjoint, with ``innermost'' blobs labelled by pasting diagrams that evaluate to zero.
   182 \end{block}
   190 \end{block}
   183 \begin{block}{}
   191 \begin{block}{}
   184 \vspace{-2mm}
   192 \vspace{-2mm}
   185 $$d_k : \bc_k \to \bc_{k-1} = {\textstyle \sum_i} (-1)^i (\text{erase blob $i$})$$
   193 $$d_k : \bc_k \to \bc_{k-1} = {\textstyle \sum_i} (-1)^i (\text{erase blob $i$})$$
   217 \begin{block}{}
   225 \begin{block}{}
   218 Taking $H_0$, this is the mapping class group acting on a TQFT skein module.
   226 Taking $H_0$, this is the mapping class group acting on a TQFT skein module.
   219 \end{block}
   227 \end{block}
   220 \end{frame}
   228 \end{frame}
   221 
   229 
       
   230 \begin{frame}{Higher Deligne conjecture}
       
   231 \begin{block}{Deligne conjecture}
       
   232 Chains on the little discs operad acts on Hochschild cohomology.
       
   233 \end{block}
       
   234 
       
   235 \begin{block}{}
       
   236 Call $\Hom{A_\infty}{\bc_*(\cM)}{\bc_*(\cM)}$ `blob cochains on $\cM$'.
       
   237 \end{block}
       
   238 
       
   239 \begin{block}{Theorem* (Higher Deligne conjecture)}
       
   240 \scalebox{0.96}{Chains on the $n$-dimensional fat graph operad acts on blob cochains.}
       
   241 \vspace{-3mm}
       
   242 $$\mathfig{.85}{tempkw/delfig2}$$
       
   243 \end{block}
       
   244 \end{frame}
       
   245 
   222 \begin{frame}{Gluing}
   246 \begin{frame}{Gluing}
   223 \begin{block}{$\bc_*(Y \times [0,1])$ is naturally an $A_\infty$ category}
   247 \begin{block}{$\bc_*(Y \times [0,1])$ is naturally an $A_\infty$ category}
   224 \begin{itemize}
   248 \begin{itemize}
   225 \item[$m_2$:] gluing $[0,1] \simeq [0,1] \cup [0,1]$
   249 \item[$m_2$:] gluing $[0,1] \simeq [0,1] \cup [0,1]$
   226 \item[$m_k$:] reparametrising $[0,1]$
   250 \item[$m_k$:] reparametrising $[0,1]$