TY  - JOUR
AU  - Fernando Galván, José Francisco
PY  - 2002
DO  - 10.1090/S0002-9947-02-02956-2
SN  - 0002-9947
UR  - https://hdl.handle.net/20.500.14352/57241
T2  - Transactions of the American Mathematical Society
AB  - Let A be an analytic ring. We show:(1) A has finite Pythagoras number if and only if its real dimension is  2, and (2) if every positive semidefinite element of A is a sum of squares, then A is real and has real dimension 2.
LA  - eng
M2  - 1909
PB  - American Mathematical Society
KW  - Analytic ring
KW  - Positive semidefnite element
KW  - Sum of squares
KW  - Pythagoras number.
TI  - Sums of squares in real analytic rings.
TY  - journal article
VL  - 354
ER  -