# Complex saddle points in QCD at finite temperature and density

Nishimura H, Ogilvie MC, Pangeni K (2014) *Physical Review D* 90(4).

Download

**No fulltext has been uploaded. References only!**

*Journal Article*|

*Original Article*|

*Published*|

*English*

No fulltext has been uploaded

Author

Department

Abstract

The sign problem in QCD at finite temperature and density leads naturally to the consideration of complex saddle points of the action or effective action. The global symmetry CK of the finite-density action, where C is charge conjugation and K is complex conjugation, constrains the eigenvalues of the Polyakov loop operator P at a saddle point in such a way that the action is real at a saddle point, and net color charge is zero. The values of TrFP and TrFP dagger at the saddle point are real but not identical, indicating the different free energy cost associated with inserting a heavy quark versus an antiquark into the system. At such complex saddle points, the mass matrix associated with Polyakov loops may have complex eigenvalues, reflecting oscillatory behavior in color-charge densities. We illustrate these properties with a simple model which includes the one-loop contribution of gluons and two flavors of massless quarks moving in a constant Polyakov loop background. Confinement-deconfinement effects are modeled phenomenologically via an added potential term depending on the Polyakov loop eigenvalues. For sufficiently large temperature T and quark chemical potential mu, the results obtained reduce to those of perturbation theory at the complex saddle point. These results may be experimentally relevant for the compressed baryonic matter experiment at FAIR.

Publishing Year

ISSN

eISSN

PUB-ID

### Cite this

Nishimura H, Ogilvie MC, Pangeni K. Complex saddle points in QCD at finite temperature and density.

*Physical Review D*. 2014;90(4).Nishimura, H., Ogilvie, M. C., & Pangeni, K. (2014). Complex saddle points in QCD at finite temperature and density.

*Physical Review D*,*90*(4). doi:10.1103/PhysRevD.90.045039Nishimura, H., Ogilvie, M. C., and Pangeni, K. (2014). Complex saddle points in QCD at finite temperature and density.

*Physical Review D*90.Nishimura, H., Ogilvie, M.C., & Pangeni, K., 2014. Complex saddle points in QCD at finite temperature and density.

*Physical Review D*, 90(4). H. Nishimura, M.C. Ogilvie, and K. Pangeni, “Complex saddle points in QCD at finite temperature and density”,

*Physical Review D*, vol. 90, 2014. Nishimura, H., Ogilvie, M.C., Pangeni, K.: Complex saddle points in QCD at finite temperature and density. Physical Review D. 90, (2014).

Nishimura, Hiromichi, Ogilvie, Michael C., and Pangeni, Kamal. “Complex saddle points in QCD at finite temperature and density”.

*Physical Review D*90.4 (2014).
This data publication is cited in the following publications:

This publication cites the following data publications:

### Export

0 Marked Publications### Web of Science

View record in Web of Science®### Sources

arXiv 1401.7982

Inspire 1279607