No proper generalized quadratic forms are universal over quadratic fields

Abstract We consider generalized quadratic forms over real quadratic number fields and prove, under a natural positive-definiteness condition, that a generalized quadratic form can only be universal if it contains a quadratic subform that is universal. We also construct an example illustrating that the positive-definiteness condition is necessary.

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Publication Details

Journal
The Ramanujan Journal
Published
2026-03-21
DOI
https://doi.org/10.1007/s11139-026-01370-0
Primary Topic
Algebraic Geometry and Number Theory
Type
article
Field-Weighted Citation Impact
0.00
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No proper generalized quadratic forms are universal over quadratic fields

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No proper generalized quadratic forms are universal over quadratic fields

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article en

Abstract

Abstract We consider generalized quadratic forms over real quadratic number fields and prove, under a natural positive-definiteness condition, that a generalized quadratic form can only be universal if it contains a quadratic subform that is universal. We also construct an example illustrating that the positive-definiteness condition is necessary.

The Ramanujan JournalVol. 69(4)
Charles University (CZ)
Reduced inequalities
Openalex Percentile: Top 12%
Algebraic Geometry and Number Theory
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