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arXiv · 1703.03185

Universal quadratic forms over multiquadratic fields

Vítězslav Kala·Josef Svoboda
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Abstract

For all positive integers $k$ and $N$ we prove that there are infinitely many totally real multiquadratic fields $K$ of degree $2^k$ over $\mathbb Q$ such that each universal quadratic form over $K$ has at least $N$ variables.

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Vítězslav Kala, Josef Svoboda. 2017-03-09. Universal quadratic forms over multiquadratic fields. https://doi.org/10.1007/s11139-017-9965-7

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