text/ncat.tex
changeset 367 5ce95bd193ba
parent 366 b69b09d24049
child 381 84bcc5fdf8c2
equal deleted inserted replaced
366:b69b09d24049 367:5ce95bd193ba
  1704 $(B^k, B^{k-1})$.
  1704 $(B^k, B^{k-1})$.
  1705 See Figure \ref{feb21a}.
  1705 See Figure \ref{feb21a}.
  1706 Another way to say this is that $(X, M)$ is homeomorphic to $B^{k-1}\times([-1,1], \{0\})$.
  1706 Another way to say this is that $(X, M)$ is homeomorphic to $B^{k-1}\times([-1,1], \{0\})$.
  1707 
  1707 
  1708 \begin{figure}[!ht]
  1708 \begin{figure}[!ht]
  1709 \begin{equation*}
  1709 $$\tikz[baseline,line width=2pt]{\draw[blue] (-2,0)--(2,0); \fill[red] (0,0) circle (0.1);} \qquad \qquad \tikz[baseline,line width=2pt]{\draw[blue] (0,0) circle (2 and 1); \draw[red] (0,1)--(0,-1);}$$
  1710 \mathfig{.85}{tempkw/feb21a}
       
  1711 \end{equation*}
       
  1712 \caption{0-marked 1-ball and 0-marked 2-ball}
  1710 \caption{0-marked 1-ball and 0-marked 2-ball}
  1713 \label{feb21a}
  1711 \label{feb21a}
  1714 \end{figure}
  1712 \end{figure}
  1715 
  1713 
  1716 The $0$-marked balls can be cut into smaller balls in various ways.
  1714 The $0$-marked balls can be cut into smaller balls in various ways.
  1749 The set $\cD$ breaks into ``blocks" according to the restrictions to the pinched points of $X\times J$
  1747 The set $\cD$ breaks into ``blocks" according to the restrictions to the pinched points of $X\times J$
  1750 (see Figure \ref{feb21b}).
  1748 (see Figure \ref{feb21b}).
  1751 These restrictions are 0-morphisms $(a, b)$ of $\cA$ and $\cB$.
  1749 These restrictions are 0-morphisms $(a, b)$ of $\cA$ and $\cB$.
  1752 
  1750 
  1753 \begin{figure}[!ht]
  1751 \begin{figure}[!ht]
  1754 \begin{equation*}
  1752 $$
  1755 \mathfig{1}{tempkw/feb21b}
  1753 \begin{tikzpicture}[blue,line width=2pt]
  1756 \end{equation*}
  1754 \draw (0,1) -- (0,-1) node[below] {$X$};
       
  1755 
       
  1756 \draw (2,0) -- (4,0) node[below] {$J$};
       
  1757 \fill[red] (3,0) circle (0.1);
       
  1758 
       
  1759 \draw (6,0) node(a) {} arc (135:90:4) node(top) {} arc (90:45:4) node(b) {} arc (-45:-90:4) node(bottom) {} arc(-90:-135:4);
       
  1760 \draw[red] (top.center) -- (bottom.center);
       
  1761 \fill (a) circle (0.1) node[left] {\color{green!50!brown} $a$};
       
  1762 \fill (b) circle (0.1) node[right] {\color{green!50!brown} $b$};
       
  1763 
       
  1764 \path (bottom) node[below]{$X \times J$};
       
  1765 
       
  1766 \end{tikzpicture}
       
  1767 $$
  1757 \caption{The pinched product $X\times J$}
  1768 \caption{The pinched product $X\times J$}
  1758 \label{feb21b}
  1769 \label{feb21b}
  1759 \end{figure}
  1770 \end{figure}
  1760 
  1771 
  1761 More generally, consider an interval with interior marked points, and with the complements
  1772 More generally, consider an interval with interior marked points, and with the complements
  1765 To this data we can apply the coend construction as in Subsection \ref{moddecss} above
  1776 To this data we can apply the coend construction as in Subsection \ref{moddecss} above
  1766 to obtain an $\cA_0$-$\cA_l$ $0$-sphere module and, forgetfully, an $n{-}1$-category.
  1777 to obtain an $\cA_0$-$\cA_l$ $0$-sphere module and, forgetfully, an $n{-}1$-category.
  1767 This amounts to a definition of taking tensor products of $0$-sphere module over $n$-categories.
  1778 This amounts to a definition of taking tensor products of $0$-sphere module over $n$-categories.
  1768 
  1779 
  1769 \begin{figure}[!ht]
  1780 \begin{figure}[!ht]
  1770 \begin{equation*}
  1781 $$
  1771 \mathfig{1}{tempkw/feb21c}
  1782 \begin{tikzpicture}[baseline,line width = 2pt]
  1772 \end{equation*}
  1783 \draw[blue] (0,0) -- (6,0);
       
  1784 \foreach \x/\n in {0.5/0,1.5/1,3/2,4.5/3,5.5/4} {
       
  1785 	\path (\x,0)  node[below] {\color{green!50!brown}$\cA_{\n}$};
       
  1786 }
       
  1787 \foreach \x/\n in {1/0,2/1,4/2,5/3} {
       
  1788 	\fill[red] (\x,0) circle (0.1) node[above] {\color{green!50!brown}$\cM_{\n}$};
       
  1789 }
       
  1790 \end{tikzpicture}
       
  1791 \qquad
       
  1792 \qquad
       
  1793 \begin{tikzpicture}[baseline,line width = 2pt]
       
  1794 \draw[blue] (0,0) circle (2);
       
  1795 \foreach \q/\n in {-45/0,90/1,180/2} {
       
  1796 	\path (\q:2.4)  node {\color{green!50!brown}$\cA_{\n}$};
       
  1797 }
       
  1798 \foreach \q/\n in {60/0,120/1,-120/2} {
       
  1799 	\fill[red] (\q:2) circle (0.1);
       
  1800 	\path (\q:2.4) node {\color{green!50!brown}$\cM_{\n}$};
       
  1801 }
       
  1802 \end{tikzpicture}
       
  1803 $$
  1773 \caption{Marked and labeled 1-manifolds}
  1804 \caption{Marked and labeled 1-manifolds}
  1774 \label{feb21c}
  1805 \label{feb21c}
  1775 \end{figure}
  1806 \end{figure}
  1776 
  1807 
  1777 We could also similarly mark and label a circle, obtaining an $n{-}1$-category
  1808 We could also similarly mark and label a circle, obtaining an $n{-}1$-category
  1796 1-marked $k$-balls can be decomposed in various ways into smaller balls, which are either 
  1827 1-marked $k$-balls can be decomposed in various ways into smaller balls, which are either 
  1797 smaller 1-marked $k$-balls or the product of an unmarked ball with a marked interval.
  1828 smaller 1-marked $k$-balls or the product of an unmarked ball with a marked interval.
  1798 We now proceed as in the above module definitions.
  1829 We now proceed as in the above module definitions.
  1799 
  1830 
  1800 \begin{figure}[!ht]
  1831 \begin{figure}[!ht]
  1801 \begin{equation*}
  1832 $$
  1802 \mathfig{.4}{tempkw/feb21d}
  1833 \begin{tikzpicture}[baseline,line width = 2pt]
  1803 \end{equation*}
  1834 \draw[blue] (0,0) circle (2);
       
  1835 \fill[red] (0,0) circle (0.1);
       
  1836 \foreach \qm/\qa/\n in {70/-30/0, 120/95/1, -120/180/2} {
       
  1837 	\draw[red] (0,0) -- (\qm:2);
       
  1838 	\path (\qa:1) node {\color{green!50!brown} $\cA_\n$};
       
  1839 	\path (\qm+20:2.5) node(M\n) {\color{green!50!brown} $\cM_\n$};
       
  1840 	\draw[line width=1pt, green!50!brown, ->] (M\n.\qm+135) to[out=\qm+135,in=\qm+90] (\qm+5:1.3);
       
  1841 }
       
  1842 \end{tikzpicture}
       
  1843 $$
  1804 \caption{Cone on a marked circle}
  1844 \caption{Cone on a marked circle}
  1805 \label{feb21d}
  1845 \label{feb21d}
  1806 \end{figure}
  1846 \end{figure}
  1807 
  1847 
  1808 A $n$-category 1-sphere module is, among other things, an $n{-}2$-category $\cD$ with
  1848 A $n$-category 1-sphere module is, among other things, an $n{-}2$-category $\cD$ with