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Page 17
A topological space X is said to be locally compact if every point has a
neighborhood whose closure is compact . A family of sets has the finite
intersection property if every finite subfamily has a non - void intersection . A
subset of X is called ...
A topological space X is said to be locally compact if every point has a
neighborhood whose closure is compact . A family of sets has the finite
intersection property if every finite subfamily has a non - void intersection . A
subset of X is called ...
Page 485
( Gantmacher ) An operator in B ( X , Y ) is weakly compact if and only if its adjoint
is weakly compact . PROOF . Let T be weakly compact . Since the closed unit
sphere S * of Y * is Y - compact ( V . 4 . 2 ) , it follows from Lemma 7 and Lemma 1
.
( Gantmacher ) An operator in B ( X , Y ) is weakly compact if and only if its adjoint
is weakly compact . PROOF . Let T be weakly compact . Since the closed unit
sphere S * of Y * is Y - compact ( V . 4 . 2 ) , it follows from Lemma 7 and Lemma 1
.
Page 494
2 we conclude that T * maps the unit sphere of X * into a conditionally weakly
compact set of rca ( S ) , and therefore T * is a weakly compact operator . By
Theorem 4 . 8 this implies that T is a weakly compact operator . Q . E . D . 4
THEOREM .
2 we conclude that T * maps the unit sphere of X * into a conditionally weakly
compact set of rca ( S ) , and therefore T * is a weakly compact operator . By
Theorem 4 . 8 this implies that T is a weakly compact operator . Q . E . D . 4
THEOREM .
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Contents
Metric Spaces | 19 |
Convergence and Uniform Convergence of Generalized | 26 |
Exercises | 33 |
Copyright | |
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