 
Summary: Issues in analytic continuation:
the critical line, spectral properties and the
average phase factor.
Massimo D'Elia
Genoa University & INFN
"Sign Problems and Complex Actions"
ECT*, Trento, March 26 2009
In collaboration with P. Cea (Bari), L. Cosmai (Bari), C. Manneschi (Genoa), A. Papa
(Cosenza) and F. Sanfilippo (Rome)
1 OUTLINE
Waiting for a definite solution to the sign problem, analytic continuation from imag
inary chemical potentials remains one of the few available methods to investigate
QCD at finite density. More efforts are needed to test its reliability and to push its
predictivity. In this talk we focus on the following issues:
· Analytic continuation of the (pseudo)critical line: precision tests in sign problem
free theories. with P. Cea (Bari), L. Cosmai (Bari), C. Manneschi (Genoa), A. Papa (Cosenza)
Is it reliable?
What is the best strategy to perform it?
· Nf = 2 QCD thermodynamics and analytic continuation from two independent
imaginary chemical potentials with F. Sanfilippo (Rome)
