F–Products and Nonstandard Hulls for Strongly Continuous One–parameter Semigroups of Linear Operators
نویسندگان
چکیده
We give an overview of the F–product construction and the corresponding nonstandard constructions and show that (in the case of bounded ultrapowers) both constructs are isomorphic (theorem 3.15). From this we also follow a little “classical” corollary (3.14). The nonstandard construction has been investigated in [Wol84] and [Wol], the corresponding classical constructions first appeared in [Der80] and [Kru90].
منابع مشابه
F-products and nonstandard hulls for semigroups
Derndinger [Der80] and Krupa [Kru90] defined the F–product of a (strongly continuous one–parameter) semigroup (of linear operators) and presented some applications (e.g. to spectral theory of positive operators, cf. [EN00]). Wolff (in [Wol84] and [Wol00]) investigated some kind of nonstandard analogon and applied it to spectral theory of group representations. The question arises in which way t...
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