Abstract
We study several field invariants arising in quadratic form theory. Some of the invariants considered are of particular interest in the study of real fields, including the length, the u-invariant, and the (reduced) stability index. In this context we give a systematic account of valuation theoretic arguments that lead to lower bounds for these invariants.
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Becher, K.J., Leep, D.B. Real fields, valuations, and quadratic forms. manuscripta math. 141, 737–754 (2013). https://doi.org/10.1007/s00229-012-0597-3
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DOI: https://doi.org/10.1007/s00229-012-0597-3