RT Journal Article
T1 Representation of positive semidefinite elements as sum of squares in 2-dimensional local rings
A1 Fernando Galván, José Francisco
AB A classical problem in real geometry concerns the representation of positive semidefinite elements of a ring A as sums of squares of elements of A. If A is an excellent ring of dimension ≥3, it is already known that it contains positive semidefinite elements that cannot be represented as sums of squares in A. The one dimensional local case has been afforded by Scheiderer (mainly when its residue field is real closed). In this work we focus on the 2-dimensional case and determine (under some mild conditions) which local excellent henselian rings A of embedding dimension 3 have the property that every positive semidefinite element of A is a sum of squares of elements of A.
PB Springer Nature
SN 1578-7303
YR 2022
FD 2022-01-09
LK https://hdl.handle.net/20.500.14352/71539
UL https://hdl.handle.net/20.500.14352/71539
LA eng
NO CRUE-CSIC (Acuerdos Transformativos 2022)
NO Ministerio de Economía, Industria y Competitividad (MINECO)
NO Universidad Complutense de Madrid
DS Docta Complutense
RD 4 abr 2025