Sharp degree bounds for sum-of-squares certificates on projective curves
نویسندگان
چکیده
منابع مشابه
Sharp Degree Bounds for Sum-of-squares Certificates on Projective Curves
Given a real projective curve with homogeneous coordinate ring R and a nonnegative homogeneous element f ∈ R, we bound the degree of a nonzero homogeneous sum-of-squares g ∈ R such that the product f g is again a sum of squares. Better yet, our degree bounds only depend on geometric invariants of the curve and we show that there exists smooth curves and nonnegative elements for which our bounds...
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ژورنال
عنوان ژورنال: Journal de Mathématiques Pures et Appliquées
سال: 2019
ISSN: 0021-7824
DOI: 10.1016/j.matpur.2018.12.010