RT Journal Article
T1 Sums of squares in real rings
A1 Fernando Galván, José Francisco
A1 Ruiz Sancho, Jesús María
A1 Scheiderer, Claus
AB 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.
PB American Mathematical Society
SN 0002-9947
YR 2004
FD 2004
LK https://hdl.handle.net/20.500.14352/49910
UL https://hdl.handle.net/20.500.14352/49910
LA eng
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DS Docta Complutense
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