Archimedean field

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This article defines a field property: a property that can be evaluated to true/false for any field.
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Definition

In terms of a subfield of the reals

An Archimedean field is a field that is isomorphic to a subfield of the field of real numbers.

In terms of a total ordering

An Archimedean field is a field with a total ordering ≤ on its elements satisfying the following:

  • 0≤1.
  • a≤b⟹−b≤−a.
  • a≤b and c≤d implies that a+c≤b+d.
  • 0≤a and b≤c implies that ab≤ac.
  • The Archimedean property: For any x∈K, there exists a natural number n such that x≤n, where the natural number n is viewed as the element of K obtained by adding 1 to itself n times.

Relation with other properties

Weaker properties