specializationSpecialization2006-11-04 06:32:422006-11-04 11:15:54Definitiongenerizationspecializationgeneric points% this is the default PlanetMath preamble. as your knowledge
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Let $X$ be a topological space and suppose that $x\in X$.
Any point $y\in \overline{\{{x}\}}$ is called a \emph{specialization point of $x$} and we write $x\rightsquigarrow y$
For $Y\subset X$ the set
$$\mathrm{Sp}(Y):=\{x\in X : \exists\, y\in Y\, y\in\overline{\{{x}\}} \}$$
is called the \emph{specialization of} $Y$.