Abstract
We characterize the forms that occur as restrictions of norm forms of octonion fields. The results are applied to forms of types E\(_6\), E\(_7\), and E\(_8\) and to positive definite forms over fields that allow a unique non-split octonion algebra, e.g., the field of rational numbers.
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Acknowledgements
The authors thank an anonymous referee for pointing out that 4.3.3 follows in the context of our present results.
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Knarr, N., Stroppel, M.J. Subforms of norm forms of octonion fields. Arch. Math. 110, 213–224 (2018). https://doi.org/10.1007/s00013-017-1129-x
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DOI: https://doi.org/10.1007/s00013-017-1129-x