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Minimal weakly isotropic forms

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Abstract

In this article weakly isotropic quadratic forms over a (formally) real field are studied. Conditions on the field are given which imply that every weakly isotropic form over that field has a weakly isotropic subform of small dimension. Fields over which every quadratic form can be decomposed into an orthogonal sum of a strongly anisotropic form and a torsion form are characterized in different ways.

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Correspondence to Karim Johannes Becher.

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Becher, K. Minimal weakly isotropic forms. Math. Z. 252, 91–102 (2006). https://doi.org/10.1007/s00209-005-0847-0

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