Related papers: QCD at small baryon number
The study of QCD phase diagram is very interesting, but we have never understood it well. This is because we face a problem at finite density in QCD. The problem is called sign problem. It causes a decrease of the calculation accuracy. This…
I review recent developments in determining the QCD phase diagram by means of lattice simulations. Since the invention of methods to side-step the sign problem a few years ago, a number of additional variants have been proposed, and…
In this review, I recall the nature and the inevitability of the "sign problem" which plagues attempts to simulate lattice QCD at finite baryon density. I present the main approaches used to circumvent the sign problem at small chemical…
We present some new results regarding simulations of finite density QCD based on a canonical approach. A previous study has shown that such simulations are feasible, at least on small lattices. In the current study, we investigate some of…
The infamous sign problem makes it impossible to probe dense (baryon density $\mu_B>0$) QCD at temperatures near or below the deconfinement threshold. As a workaround, one can explore QCD-like theories such as two-colour QCD (QC2D) which…
The behavior of QCD at high baryon density and low temperature is crucial to understanding the properties of neutron stars and gravitational waves emitted during their mergers. In this paper we study small systems of baryons in periodic…
The phase diagram of QCD at finite temperature and density is discussed. Large numbers of quark colors, $N_{\rm c} >> 1$, is used to explain generic features of the phase diagram. For temperatures below $ T \le 160$~MeV at zero baryon…
We demonstrate how to locate the critical endpoint of the QCD phase transition by means of simulations at imaginary \mu. For the three flavor theory, we present numerical results for the pseudo-critical line as a function of chemical…
QCD at non-zero baryon density is expected to have a critical point where the zero-density cross-over turns into a first order phase transition. To identify this point we scan the density-temperature space using a canonical ensemble method.…
We show that current experimental knowledge of QCD together with general model independent arguments such as continuity, universality and thermodynamic relations, as well as the information gained from various models can be used to…
We discuss the non-zero baryon number formulation of QCD in the quenched limit at finite temperature. This describes the thermodynamics of gluons in the background of static quark sources. Although a sign problem remains in this theory, our…
We study the baryon-quark phase transition in a molecular dynamics (MD) of quark degrees of freedom at finite temperature and density. The baryon state at low density and temperature, and the deconfined quark state at high density and…
High order cumulants of the baryon number distribution are calculated in a 2+1 flavor low energy effective model. Quantum fluctuations are encoded through the functional renormalization group approach. The chiral and deconfinement phase…
We present an overview of the arguments which lead to the picture that at low temperatures the QCD matter not far above a critical confinement-deconfinement density exists in one of several distinct superfluid phases exhibiting the quantum…
In this thesis the finite temperature transition between confined and deconfined matter is studied at zero and nonzero quark densities. The findings are relevant for the understanding of the evolution of the early Universe and contemporary…
Current status of theoretical researches on the QCD phase diagram at finite temperature and baryon chemical potential is reviewed with special emphasis on the origin of various phases and their symmetry breaking patterns. Topics include;…
I make a brief review about the QCD phases and the equation of state inferred from the neutron star data. Along the temperature axis at low baryon density, the QCD phase transition is a smooth crossover, and it is a natural extension of our…
We summarize our recent results for the (T,mu)-phase diagram of N_f=3 QCD. Finding a strong variation of the critical endpoint mu_c with the quark mass m, we point out that an endpoint within reach of experiment requires fine-tuned quark…
For a long time, strong coupling expansions have not been applied systematically in lattice QCD thermodynamics, in view of the succes of numerical Monte Carlo studies. The persistent sign problem at finite baryo-chemical potential, however,…
We derive exact constraints relating QCD at nonzero baryon chemical potential and temperature to QCD at nonzero isospin chemical potential and temperature, a theory which can be simulated by conventional methods. These results challenge the…