Sums of squares of polynomials with rational coefficients
نویسندگان
چکیده
منابع مشابه
Sums of Squares of Polynomials with Rational Coefficients
We construct families of explicit polynomials f over Q that are sums of squares of polynomials over R, but not over Q. Whether or not such examples exist was an open question originally raised by Sturmfels. We also study representations of f as sums of squares of rational functions over Q. In the case of ternary quartics, we prove that our counterexamples to Sturmfels’ question are the only ones.
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ژورنال
عنوان ژورنال: Journal of the European Mathematical Society
سال: 2016
ISSN: 1435-9855
DOI: 10.4171/jems/620