Non-standard model

In model theory, a discipline within mathematical logic, a non-standard model is a model of a theory that is not isomorphic to the intended model (or standard model).[1]

Existence

If the intended model is infinite and the language is first-order, then the Löwenheim–Skolem theorems guarantee the existence of non-standard models. The non-standard models can be chosen as elementary extensions or elementary substructures of the intended model.

Importance

Non-standard models are studied in set theory, non-standard analysis and non-standard models of arithmetic.

gollark: Anyway, the main issue I see with genetically engineering child super-soldiers is that the children can't really consent to said modification, especially if it's before they're born.
gollark: I... haven't heard about them doing that?
gollark: > If you consider the “standard of living” to be something we should make effort improve in a utilitarian philosophy senseis just assuming utilitarian philosophy is "right".
gollark: 'Tis the is-ought problem.
gollark: Somewhat more implicitly.

See also

References

  1. Roman Kossak, 2004 Nonstandard Models of Arithmetic and Set Theory American Mathematical Soc.
This article is issued from Wikipedia. The text is licensed under Creative Commons - Attribution - Sharealike. Additional terms may apply for the media files.