Nearstandardness of finite set

Author
T. Kudryk, V. Lyantse, G. Chuiko
Department of Mechanics and Mathematics, Lviv University, Universytetska 1, Lviv, 290602, Ukraine
Abstract
On the set ${\Bbb T}$, finite in the sense of the E.Nelson's Internal Set Theory, a measure $\nu$ is given. For ''discrete integral'' $\Sigma_{t\in{\Bbb T}}x(t)\nu\{t\},\,x\in{\Bbb C}^{\Bbb T}$ the analogs of the classical theorems of Lebesgue integral theory are regarded. As the set ${\Bbb T}$ is nonstandard, for the measures and functions given on it, a direct definition of nearstandardness is impossible. Indirect way based on the embedding of the algebra $2^{\Bbb T}$ into the algebra $2^{\text{\bf T}}$ is used. Here, {\bf T} is a standard set. Relations between nearstandard charges and their shadows, as well as nearstandard functions and their shadows appearing with such approach are investigated.
Keywords
Internal Set Theory, finite set, measure, discrete integral, Lebesgue integral, nonstandard analysis, nearstandardness
DOI
doi:10.30970/ms.2.1.25-34
Reference
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Pages
25-34
Volume
2
Issue
1
Year
1993
Journal
Matematychni Studii
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