RT Journal Article
T1 On Hilbert's 17th problem and Pfister's multiplicative formulae for the ring of real analytic functions
A1 Acquistapace, Francesca
A1 Broglia, Fabrizio
A1 Fernando Galván, José Francisco
AB In this work, we present "infinite" multiplicative formulae for countable collections of sums of squares (of meromorphic functions on R-n). Our formulae generalize the classical Pfister's ones concerning the representation as a sum of 2(r) squares of the product of two elements of a field K which are sums of 2(r) squares. As a main application, we reduce the representation of a positive semidefinite analytic function on R-n as a sum of squares to the representation as sums of squares of its special factors. Recall that roughly speaking a special factor is an analytic function on R-n which has just one complex irreducible factor and whose zeroset has dimension between 1 and n - 2.
PB SCUOLA NORMALE SUPERIORE DI PISA
SN 0391-173X
YR 2014
FD 2014
LK https://hdl.handle.net/20.500.14352/33652
UL https://hdl.handle.net/20.500.14352/33652
LA eng
NO Italian GNSAGA of INdAM
NO MIUR
NO Spanish GAAR
NO GAAR Grupos
DS Docta Complutense
RD 8 abr 2025