Related papers: Fluctuations, correlations and the sign problem in…
Baryon number fluctuations are sensitive to the QCD phase transition and QCD critical point. According to the Feynman rules of finite-temperature field theory, we calculated various order moments and cumulants of the baryon number…
We apply optimized perturbation theory to the quark-meson model at finite temperature T and quark chemical potential mu. The effective potential is calculated to one loop both in the chiral limit and at the physical point and used to study…
We study the effect of quantum and thermal fluctuations as well as the mass dependence of the phase structure of QCD at finite temperature and density within a dynamical Polyakov-loop--extended quark-meson model. The glue dynamics is…
We analytically study two-color QCD with an even number of flavors at high baryon density. This theory is free from the fermion sign problem. Chiral symmetry is broken spontaneously by the diquark condensate. Based on the symmetry breaking…
Lattice QCD with staggered quarks is augmented by the addition of a chiral 4-fermion interaction. The Dirac operator is now non-singular at $m_q=0$, decreasing the computing requirements for light quark simulations by at least an order of…
We investigate the finite-temperature quantum chromodynamics (QCD) on a rotating lattice with $N_f=2+1$ staggered fermions and the projective plane boundary condition. We observe a negative rotational rigidity (defined in the main text) and…
We point out that the quartic cumulant (and kurtosis) of the order parameter fluctuations is universally negative when the critical point is approached on the crossover side of the phase separation line. As a consequence, the kurtosis of a…
In a local gauge-invariant theory with massless Dirac fermions a symmetry of the Lorentz-invariant fermion charge is larger than a symmetry of the Lagrangian as a whole. While the Dirac Lagrangian exhibits only a chiral symmetry, the…
I show an updated QCD phase diagram with recent developments from chiral effective theories and phenomenological models. Expected signals of a QCD critical point accessible in heavy-ion collisions are also discussed. In particular,…
QCD at finite isospin chemical potential mu_I has no fermion sign problem and can be studied on the lattice. We solve this theory analytically in two limits: at low mu_I where chiral perturbation theory is applicable, and at asymptotically…
A nonperturbative lattice study of QCD at finite chemical potential is complicated due to the complex fermion determinant and the sign problem. Here we apply the method of stochastic quantization and complex Langevin dynamics to this…
We investigate the impact of the matter and glue dynamics on baryon number fluctuations and the kurtosis of baryon number distribution. This is done within the framework of QCD-improved low energy effective models. In particular we include…
We study physics at temperatures just above the QCD phase transition (Tc) using chiral (overlap) Fermions in the quenched approximation of lattice QCD. Exact zero modes of the overlap Dirac operator are localized and their frequency of…
We investigate the effect of screening of the four-quarks contact interactions by the ring diagram at finite temperature and density in an effective chiral model inspired by QCD in the Coulomb gauge. As a consequence, a medium-dependent…
We study a longstanding problem in lattice QCD at low temperature and nonzero quark chemical potential on an onset of the quark number density at $\mu=m_\pi/2$. We introduce a physical parametrization of the eigenvalues in the reduction…
We study the QCD phase diagram at finite temperature and baryon chemical potential by relating the behavior of the light-quark condensate to the threshold energy for the onset of perturbative QCD. These parameters are connected to the…
We discuss the dependence of observables on the chemical potential in 't Hooft's large-N QCD. To this end we use the worldline formalism to expand the fermionic determinant in powers of 1/N. We consider the hadronic as well as the…
We calculate the chiral condensate of QCD with 2, 2+1 and 3 flavors of sea quarks. Lattice QCD simulations are performed employing dynamical overlap fermions with up and down quark masses covering a range between 3 and 100 MeV. On L ~…
Recently it has been found that quantum chromodynamics (QCD) phase diagram possesses a duality between chiral symmetry breaking and pion condensation. For the first time this was revealed in the QCD motivated toy model. Then it was…
Integrating over a continuum Majorana fermion formally yields a functional pfaffian. We show that the phase of this pfaffian is ambiguous, as it depends on the choice of basis. This ambiguity is naturally resolved within a non-perturbative…