text/ncat.tex
changeset 530 b236746e8e4d
parent 529 8e055b7c0768
child 531 da9bf150bf3d
equal deleted inserted replaced
529:8e055b7c0768 530:b236746e8e4d
  1637 the above antirefinements of the fixed interval $J$, but with the rightmost subinterval $I_m$ always
  1637 the above antirefinements of the fixed interval $J$, but with the rightmost subinterval $I_m$ always
  1638 omitted.
  1638 omitted.
  1639 More specifically, $D\to D'$ is an antirefinement if $D'$ is obtained from $D$ by 
  1639 More specifically, $D\to D'$ is an antirefinement if $D'$ is obtained from $D$ by 
  1640 gluing subintervals together and/or omitting some of the rightmost subintervals.
  1640 gluing subintervals together and/or omitting some of the rightmost subintervals.
  1641 (See Figure \ref{fig:lmar}.)
  1641 (See Figure \ref{fig:lmar}.)
  1642 \begin{figure}[t]$$
  1642 \begin{figure}[t] \centering
  1643 \definecolor{arcolor}{rgb}{.75,.4,.1}
  1643 \definecolor{arcolor}{rgb}{.75,.4,.1}
  1644 \begin{tikzpicture}[line width=1pt]
  1644 \begin{tikzpicture}[line width=1pt]
  1645 \fill (0,0) circle (.1);
  1645 \fill (0,0) circle (.1);
  1646 \draw (0,0) -- (2,0);
  1646 \draw (0,0) -- (2,0);
  1647 \draw (1,0.1) -- (1,-0.1);
  1647 \draw (1,0.1) -- (1,-0.1);
  1677 \foreach \x in {1.0, 1.5} {
  1677 \foreach \x in {1.0, 1.5} {
  1678 	\draw (\x,1.1) -- (\x,0.9);
  1678 	\draw (\x,1.1) -- (\x,0.9);
  1679 }
  1679 }
  1680 
  1680 
  1681 \end{tikzpicture}
  1681 \end{tikzpicture}
  1682 $$
       
  1683 \caption{Antirefinements of left-marked intervals}\label{fig:lmar}\end{figure}
  1682 \caption{Antirefinements of left-marked intervals}\label{fig:lmar}\end{figure}
  1684 
  1683 
  1685 Now we define the chain complex $\hom_\cC(\cX_\cC \to \cY_\cC)$.
  1684 Now we define the chain complex $\hom_\cC(\cX_\cC \to \cY_\cC)$.
  1686 The underlying vector space is 
  1685 The underlying vector space is 
  1687 \[
  1686 \[
  1733 \]
  1732 \]
  1734 for each left-marked interval $K$.
  1733 for each left-marked interval $K$.
  1735 These are required to commute with gluing;
  1734 These are required to commute with gluing;
  1736 for each subdivision $K = I_1\cup\cdots\cup I_q$ the following diagram commutes:
  1735 for each subdivision $K = I_1\cup\cdots\cup I_q$ the following diagram commutes:
  1737 \[ \xymatrix{
  1736 \[ \xymatrix{
  1738 	\cX(I_1)\ot\cC(I_2)\ot\cdots\ot\cC(I_q) \ar[r]^{h_{I_0}\ot \id} 
  1737 	\cX(I_1)\ot\cC(I_2)\ot\cdots\ot\cC(I_q) \ar[r]^{h_{I_1}\ot \id} 
  1739 							\ar[d]_{\gl} & \cY(I_1)\ot\cC(I_2)\ot\cdots\ot\cC(I_q) 
  1738 							\ar[d]_{\gl} & \cY(I_1)\ot\cC(I_2)\ot\cdots\ot\cC(I_q) 
  1740 								\ar[d]^{\gl} \\
  1739 								\ar[d]^{\gl} \\
  1741 	\cX(K) \ar[r]^{h_{K}} & \cY(K)
  1740 	\cX(K) \ar[r]^{h_{K}} & \cY(K)
  1742 } \]
  1741 } \]
  1743 Given such an $h$ we can construct a morphism $g$, with $\bd g = 0$, as follows.
  1742 Given such an $h$ we can construct a morphism $g$, with $\bd g = 0$, as follows.
  1873 The product is pinched over the boundary of $J$.
  1872 The product is pinched over the boundary of $J$.
  1874 The set $\cD$ breaks into ``blocks" according to the restrictions to the pinched points of $X\times J$
  1873 The set $\cD$ breaks into ``blocks" according to the restrictions to the pinched points of $X\times J$
  1875 (see Figure \ref{feb21b}).
  1874 (see Figure \ref{feb21b}).
  1876 These restrictions are 0-morphisms $(a, b)$ of $\cA$ and $\cB$.
  1875 These restrictions are 0-morphisms $(a, b)$ of $\cA$ and $\cB$.
  1877 
  1876 
  1878 \begin{figure}[t]
  1877 \begin{figure}[t] \centering
  1879 $$
       
  1880 \begin{tikzpicture}[blue,line width=2pt]
  1878 \begin{tikzpicture}[blue,line width=2pt]
  1881 \draw (0,1) -- (0,-1) node[below] {$X$};
  1879 \draw (0,1) -- (0,-1) node[below] {$X$};
  1882 
  1880 
  1883 \draw (2,0) -- (4,0) node[below] {$J$};
  1881 \draw (2,0) -- (4,0) node[below] {$J$};
  1884 \fill[red] (3,0) circle (0.1);
  1882 \fill[red] (3,0) circle (0.1);
  1889 \fill (b) circle (0.1) node[right] {\color{green!50!brown} $b$};
  1887 \fill (b) circle (0.1) node[right] {\color{green!50!brown} $b$};
  1890 
  1888 
  1891 \path (bottom) node[below]{$X \times J$};
  1889 \path (bottom) node[below]{$X \times J$};
  1892 
  1890 
  1893 \end{tikzpicture}
  1891 \end{tikzpicture}
  1894 $$
       
  1895 \caption{The pinched product $X\times J$}
  1892 \caption{The pinched product $X\times J$}
  1896 \label{feb21b}
  1893 \label{feb21b}
  1897 \end{figure}
  1894 \end{figure}
  1898 
  1895 
  1899 More generally, consider an interval with interior marked points, and with the complements
  1896 More generally, consider an interval with interior marked points, and with the complements
  1902 (See Figure \ref{feb21c}.)
  1899 (See Figure \ref{feb21c}.)
  1903 To this data we can apply the coend construction as in \S\ref{moddecss} above
  1900 To this data we can apply the coend construction as in \S\ref{moddecss} above
  1904 to obtain an $\cA_0$-$\cA_l$ $0$-sphere module and, forgetfully, an $n{-}1$-category.
  1901 to obtain an $\cA_0$-$\cA_l$ $0$-sphere module and, forgetfully, an $n{-}1$-category.
  1905 This amounts to a definition of taking tensor products of $0$-sphere modules over $n$-categories.
  1902 This amounts to a definition of taking tensor products of $0$-sphere modules over $n$-categories.
  1906 
  1903 
  1907 \begin{figure}[t]
  1904 \begin{figure}[t] \centering
  1908 $$
       
  1909 \begin{tikzpicture}[baseline,line width = 2pt]
  1905 \begin{tikzpicture}[baseline,line width = 2pt]
  1910 \draw[blue] (0,0) -- (6,0);
  1906 \draw[blue] (0,0) -- (6,0);
  1911 \foreach \x/\n in {0.5/0,1.5/1,3/2,4.5/3,5.5/4} {
  1907 \foreach \x/\n in {0.5/0,1.5/1,3/2,4.5/3,5.5/4} {
  1912 	\path (\x,0)  node[below] {\color{green!50!brown}$\cA_{\n}$};
  1908 	\path (\x,0)  node[below] {\color{green!50!brown}$\cA_{\n}$};
  1913 }
  1909 }
  1925 \foreach \q/\n in {60/0,120/1,-120/2} {
  1921 \foreach \q/\n in {60/0,120/1,-120/2} {
  1926 	\fill[red] (\q:2) circle (0.1);
  1922 	\fill[red] (\q:2) circle (0.1);
  1927 	\path (\q:2.4) node {\color{green!50!brown}$\cM_{\n}$};
  1923 	\path (\q:2.4) node {\color{green!50!brown}$\cM_{\n}$};
  1928 }
  1924 }
  1929 \end{tikzpicture}
  1925 \end{tikzpicture}
  1930 $$
       
  1931 \caption{Marked and labeled 1-manifolds}
  1926 \caption{Marked and labeled 1-manifolds}
  1932 \label{feb21c}
  1927 \label{feb21c}
  1933 \end{figure}
  1928 \end{figure}
  1934 
  1929 
  1935 We could also similarly mark and label a circle, obtaining an $n{-}1$-category
  1930 We could also similarly mark and label a circle, obtaining an $n{-}1$-category
  1954 A 1-marked $k$-ball can be decomposed in various ways into smaller balls, which are either 
  1949 A 1-marked $k$-ball can be decomposed in various ways into smaller balls, which are either 
  1955 (a) smaller 1-marked $k$-balls, (b) 0-marked $k$-balls, or (c) plain $k$-balls.
  1950 (a) smaller 1-marked $k$-balls, (b) 0-marked $k$-balls, or (c) plain $k$-balls.
  1956 (See Figure \nn{need figure}.)
  1951 (See Figure \nn{need figure}.)
  1957 We now proceed as in the above module definitions.
  1952 We now proceed as in the above module definitions.
  1958 
  1953 
  1959 \begin{figure}[!ht]
  1954 \begin{figure}[t] \centering
  1960 $$
       
  1961 \begin{tikzpicture}[baseline,line width = 2pt]
  1955 \begin{tikzpicture}[baseline,line width = 2pt]
  1962 \draw[blue][fill=blue!15!white] (0,0) circle (2);
  1956 \draw[blue][fill=blue!15!white] (0,0) circle (2);
  1963 \fill[red] (0,0) circle (0.1);
  1957 \fill[red] (0,0) circle (0.1);
  1964 \foreach \qm/\qa/\n in {70/-30/0, 120/95/1, -120/180/2} {
  1958 \foreach \qm/\qa/\n in {70/-30/0, 120/95/1, -120/180/2} {
  1965 	\draw[red] (0,0) -- (\qm:2);
  1959 	\draw[red] (0,0) -- (\qm:2);
  1966 	\path (\qa:1) node {\color{green!50!brown} $\cA_\n$};
  1960 	\path (\qa:1) node {\color{green!50!brown} $\cA_\n$};
  1967 	\path (\qm+20:2.5) node(M\n) {\color{green!50!brown} $\cM_\n$};
  1961 	\path (\qm+20:2.5) node(M\n) {\color{green!50!brown} $\cM_\n$};
  1968 	\draw[line width=1pt, green!50!brown, ->] (M\n.\qm+135) to[out=\qm+135,in=\qm+90] (\qm+5:1.3);
  1962 	\draw[line width=1pt, green!50!brown, ->] (M\n.\qm+135) to[out=\qm+135,in=\qm+90] (\qm+5:1.3);
  1969 }
  1963 }
  1970 \end{tikzpicture}
  1964 \end{tikzpicture}
  1971 $$
       
  1972 \caption{Cone on a marked circle}
  1965 \caption{Cone on a marked circle}
  1973 \label{feb21d}
  1966 \label{feb21d}
  1974 \end{figure}
  1967 \end{figure}
  1975 
  1968 
  1976 A $n$-category 1-sphere module is, among other things, an $n{-}2$-category $\cD$ with
  1969 A $n$-category 1-sphere module is, among other things, an $n{-}2$-category $\cD$ with