TY  - CONF
A1  - Philipsen, Owe
T1  - Lattice calculations at non-zero chemical potential: the QCD phase diagram
T2  - Proceedings of Science
N2  - The so-called sign problem of lattice QCD prohibits Monte Carlo simulations at finite baryon
density by means of importance sampling. Over the last few years, methods have been developed
which are able to circumvent this problem as long as the quark chemical potential is m=T <~1.
After a brief review of these methods, their application to a first principles determination of the
QCD phase diagram for small baryon densities is summarised. The location and curvature of the
pseudo-critical line of the quark hardon transition is under control and extrapolations to physical
quark masses and the continuum are feasible in the near future. No definite conclusions can as
yet be drawn regarding the existence of a critical end point, which turns out to be extremely quark
mass and cut-off sensitive. Investigations with different methods on coarse lattices show the lightmass
chiral phase transition to weaken when a chemical potential is switched on. If persisting on
finer lattices, this would imply that there is no chiral critical point or phase transition for physical
QCD. Any critical structure would then be related to physics other than chiral symmetry breaking.
Y1  - 2009
UR  - http://publikationen.ub.uni-frankfurt.de/frontdoor/index/index/docId/27287
UR  - https://nbn-resolving.org/urn:nbn:de:hebis:30:3-272873
SN  - 1824-8039
N1  - 8th Conference Quark Confinement and the Hadron Spectrum, September 1-6, 2008, Mainz, Germany
VL  - 2009
IS  - Confinement8: 011
PB  - Scuola Internazionale Superiore di Studi Avanzati, SISSA
CY  - Trieste
ER  -