Submission: 2012, May 26
A recently found local-global principle for quadratic forms over function fields of curves over a complete discrete valued field is applied to the study of quadratic forms, sums of squares, and related field invariants.
2010 Mathematics Subject Classification: 11E04, 11E10, 11E25, 12D15, 12F20, 12J10, 14H05
Keywords and Phrases: isotropy, local-global principle, real field, sums of squares
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