A Nichtnegativstellensatz for polynomials in noncommuting variables
نویسندگان
چکیده
منابع مشابه
A Nichtnegativstellensatz for Polynomials in Noncommuting Variables
Let S ∪ {f} be a set of symmetric polynomials in noncommuting variables. If f satisfies a polynomial identity P i h ∗ i fhi = 1 + P i g ∗ i sigi for some si ∈ S ∪ {1}, then f is obviously nowhere negative semidefinite on the class of tuples of non-zero operators defined by the system of inequalities s ≥ 0 (s ∈ S). We prove the converse under the additional assumption that the quadratic module g...
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ژورنال
عنوان ژورنال: Israel Journal of Mathematics
سال: 2007
ISSN: 0021-2172,1565-8511
DOI: 10.1007/s11856-007-0070-2