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Title: On ternary quadratic forms over the rational numbers (English)
Author: Jafari, Amir
Author: Rostamkhani, Farhood
Language: English
Journal: Czechoslovak Mathematical Journal
ISSN: 0011-4642 (print)
ISSN: 1572-9141 (online)
Volume: 72
Issue: 4
Year: 2022
Pages: 1105-1119
Summary lang: English
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Category: math
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Summary: For a ternary quadratic form over the rational numbers, we characterize the set of rational numbers represented by that form over the rational numbers. Consequently, we reprove the classical fact that any positive definite integral ternary quadratic form must fail to represent infinitely many positive integers over the rational numbers. Our proof uses only the quadratic reciprocity law and the Hasse-Minkowski theorem, and is elementary. (English)
Keyword: ternary quadratic forms
Keyword: Gauss reciprocity law
Keyword: Hasse-Minkowski theorem
MSC: 11A15
MSC: 11D09
idZBL: Zbl 07655786
idMR: MR4517599
DOI: 10.21136/CMJ.2022.0359-21
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Date available: 2022-11-28T11:39:31Z
Last updated: 2023-04-11
Stable URL: http://hdl.handle.net/10338.dmlcz/151133
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