Theory of formally real fields
= Theory of formally real fields
{title2=$\mathrm{FRF}$}
= FRF
{c}
{synonym}
The theory of formally real fields consists of the <field> axioms and all sentences asserting that $-1$ is not a sum of $m$ squares, one for each positive integer $m$. The <real closure theorem> and model completeness make the <Theory of real closed fields> its <model companion>.