Abstract
LetF be a formally real function field (i.e., −1 is not a sum of squares inF) of transcendence degreen over ℝ. LetA be a finitely generated ℝ-subalgebra ofF whose field of quotients isF. The real holomorphy ringH(F|A) ofF overA is the intersection of all valuation rings ofF which containA and have formally real residue field. The ringH(F|A) has been extensively studied and applied by Becker, Schülting and others. It is known to be a Prüfer domain of Krull dimension not exceedingn and from this it can be shown that every finitely generated ideal ofH(F|A) can be generated byn+1 elements. Here, assuming thatA is regular (i.e., every localization with respect to a prime ideal is regular local), we give necessary and sufficient topological conditions in order for every finitely generated ideal ofH(F|A) to admitn generators. We also provide a geometric description ofH(F|A).
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Buchner, M.A., Kucharz, W. On relative real holomorphy rings. Manuscripta Math 63, 303–316 (1989). https://doi.org/10.1007/BF01168373
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DOI: https://doi.org/10.1007/BF01168373