ar X iv : 0 71 1 . 10 06 v 2 [ m at h . FA ] 1 3 Fe b 20 08 CONTINUOUS EXTENSION OF A DENSELY PARAMETERIZED SEMIGROUP
نویسنده
چکیده
Let S be a dense sub-semigroup of R+, and let X be a separable, reflexive Banach space. This note contains a proof that every weakly continuous contractive semigroup of operators on X over S can be extended to a weakly continuous semigroup over R+. We obtain similar results for nonlinear, nonexpansive semigroups as well. As a corollary we characterize all densely parametrized semigroups which are extendable to semigroups over R+.
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ar X iv : 0 71 1 . 10 06 v 1 [ m at h . FA ] 7 N ov 2 00 7 CONTINUOUS EXTENSION OF A DENSELY PARAMETERIZED
Let S be a dense sub-semigroup of R+, and let X be a separable, reflexive Banach space. This note contains a proof that every weakly continuous contractive semigroup of operators on X over S can be extended to a weakly continuous semigroup over R+. We obtain similar results for nonlinear, non-expansive semigroups as well. As a corollary we characterize all densely parametrized semigroups which ...
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