Positive polynomials and sequential closures of quadratic modules
نویسندگان
چکیده
منابع مشابه
Positive Polynomials and Sequential Closures of Quadratic Modules
Let S = {x ∈ Rn | f1(x) ≥ 0, . . . , fs(x) ≥ 0} be a basic closed semi-algebraic set in Rn and let PO(f1, . . . , fs) be the corresponding preordering in R[X1, . . . , Xn]. We examine for which polynomials f there exist identities f + εq ∈ PO(f1, . . . , fs) for all ε > 0. These are precisely the elements of the sequential closure of PO(f1, . . . , fs) with respect to the finest locally convex ...
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ژورنال
عنوان ژورنال: Transactions of the American Mathematical Society
سال: 2009
ISSN: 0002-9947,1088-6850
DOI: 10.1090/s0002-9947-09-05001-6