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Sums of squares in real rings


Fernando Galván, José Francisco y Ruiz Sancho, Jesús María y Scheiderer, Claus (2004) Sums of squares in real rings. Transactions of the American Mathematical Society, 356 (7). pp. 2663-2684. ISSN 0002-9947

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Let A be an excellent ring. We show that if the real dimension of A is at least three then A has in finite Pythagoras number, and there exists a positive semidefinite element in A which is not a sum of squares in A.

Tipo de documento:Artículo
Palabras clave:Positive semi-definite polynomial; Excellent ring; Real spectrum; Complete local ring
Materias:Ciencias > Matemáticas > Teoría de números
Ciencias > Matemáticas > Geometria algebraica
Código ID:15168

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Última Modificación:06 Feb 2014 10:18

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