wedge product of pointed topological spacesWedgeProductOfPointedTopologicalSpaces2009-02-13 23:03:532009-02-13 23:06:20Definition% this is the default PlanetMath preamble. as your knowledge
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{\bf Definition.} Let $\{(X_i,x_i)\}_{i\in I}$ be a finite family of disjoint pointed topological spaces. The \emph{wedge product} of these spaces is
$$\bigvee_{i\in I} X_i = \left(\bigcup_{i\in I} X_i\right) / \{x_i: i\in I\}.$$
This can be generalized to arbitrary families of pointed topological spaces, although this may require that the topology on $\bigcup_{i\in I} X_i$ satisfy a coherence condition (see \cite{Munkres}).
\begin{thebibliography} {9}
\bibitem{Munkres} Munkres, J. R. (2000). \emph{Topology} (2nd. ed.). Upper Saddle River, NJ: Prentice Hall.
\bibitem{Prasolov} Prasolov, V. V. (2004). \emph{Elements of combinatorial and differential topology}. Providence, RI: American Mathematical Society.
\bibitem{Shick} Shick, P. L. (2007). \emph{Topology: Point-set and geometric}. Hoboken, NJ: John Wiley \& Sons.
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