Interior of a set
in a topological space
The set of interior points of (cf. Interior point of a set). It is usually denoted by . Invariably, , where is the boundary of . The interior of is also equal to the union of all subsets of that are open in the entire space. The interior of a set is sometimes known as the open kernel.
Interior of a set. Encyclopedia of Mathematics. URL: http://encyclopediaofmath.org/index.php?title=Interior_of_a_set&oldid=14280