Abstract
For \(L/K\) a finite extension of algebraic number fields, L may or may not have a relative integral basis over K. We show the existence of relative integral basis of a biquadratic field \(L=\mathbb{Q}(\sqrt{m},\sqrt{n})\) over its quadratic subfield \(K=\mathbb{Q}(\sqrt{m})\) is equivalent to that K is a Pólya field, or equivalently all strongly ambiguous ideal classes of K are trivial.
Similar content being viewed by others
References
J. L. Chabert, From Pólya fields to Pólya groups. (I): Galois extensions, J. Number Theory, 203 (2019), 360–375
D. Hilbert, The Theory of Algebraic Number Fields (English summary), translated from the German and with a preface by Iain T. Adamson, with an introduction by Franz Lemmermeyer and Norbert Schappacher, Springer-Verlag (Berlin, 1998)
Leriche, A.: Cubic, quartic and sextic Pólya fields. J. Number Theory 133, 59–71 (2013)
Maarefparvar, A., Rajaei, A.: Pólya \(S_3\)-extensions of \(\mathbb{Q}\). Proc. Roy. Soc. Edinburgh Sect. A 149, 1421–1433 (2019)
Maarefparvar, A., Rajaei, A.: Relative Pólya group and Pólya dihedral extensions of \(\mathbb{Q}\). J. Number Theory 207, 367–384 (2020)
Mann, H.B.: On integral bases. Proc. Amer. Math. Soc. 9, 167–172 (1958)
W. Narkiewicz, Elementary and Analytic Theory of Algebraic Numbers, Springer-Verlag (Berlin, 2004)
Ostrowski, A.: Über ganzwertige Polynome in algebraischen Zahlkörpern. J. Reine Angew. Math. 149, 117–124 (1919)
Pólya, G.: Über ganzwertige Polynome in algebraischen Zahlkörpern. J. Reine Angew. Math. 149, 97–116 (1919)
Williams, K.S.: Integers of biquadratic fields. Canad. Math. Bull. 13, 519–526 (1970)
Zantema, H.: Integer valued polynomials over a number field. Manuscripta Math. 40, 155–203 (1982)
Acknowledgement
The author would like to thank the anonymous referee for many useful comments and suggestions.
Author information
Authors and Affiliations
Corresponding author
Additional information
This research was supported by a grant from IPM.
Rights and permissions
About this article
Cite this article
Maarefparvar, A. Existence of relative integral basis over quadratic fields and Pólya property. Acta Math. Hungar. 164, 593–598 (2021). https://doi.org/10.1007/s10474-021-01158-2
Received:
Revised:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s10474-021-01158-2