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Local Compactnesst In this section we study the notion of local compactness, and we prove the basic
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Local Compactnesst In this section we study the notion of local compactness, and we prove the basic theorem that any locally compact Hausdorff space can be imbedded in a certain compact Hausdorff space, called its one-point compactification. Definition. A space X is said to be locally compact at x if there is some compact subset C of X that contains a neighborhood of x. If X is locally compact at each of its points, X is said simply to be locally compact. This section will be assumed in 35-3, in Chapter 7, and in 88-12. Chap 3 $ 3-8 ring of Local Compactness 183 Note that a compact space is automatically locally compact. EXAMPLE 1. The real line R is locally compact. The point x lies in some interval (a, b), which in turn is contained in the compact set (a, b). The sub- space of rational numbers is not locally compact, as you can check. Eon of EXAMPLE 2. The space R* is locally compact; the point x lies in some basis element (a,b) x.. x (a.. b.), which in turn lies in the compact set