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On the pythagoras numbers of real analytic set germs.


Fernando Galván, José Francisco y Ruiz Sancho, Jesús María (2005) On the pythagoras numbers of real analytic set germs. Bulletin de la Société Mathématique de France , 133 (3). pp. 349-362. ISSN 0037-9484

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We Show that (i) the Pythagoras number of a real analytic set germ is the supremum of the Pythagoras numbers of the curve germs it contains, and (ii) every real analytic curve germ is contained in a real analytic surface germ with the same Pythagoras number (or Pythagoras number 2 if the curve is Pythagorean). This gives new examples and counterexamples concerning sums of squares and positive semidefinite analytic function germs.

Tipo de documento:Artículo
Palabras clave:Pythagoras number; sum of squares; M. Artin’s approximation.
Materias:Ciencias > Matemáticas > Geometria algebraica
Código ID:15159

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Última Modificación:06 Feb 2014 10:17

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