Fields Maximal with Respect to a Set of Orderings

نویسنده

  • THOMAS C. CRAVEN
چکیده

Using Zorn’s lemma one can show that order closures always exist [Cl, Sect. 43. This is the first systematic treatment of such fields, though they have also been used in [C2]. A major problem in dealing with order closed fields is that it is not clear whether or not they have algebraic extensions to which all orderings extend (necessarily nonuniquely). This leads us to make the following definition.

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تاریخ انتشار 2003