Related papers: Patterns of Symmetry Breaking in QCD at High Baryo…
The breaking of flavor SU(3) symmetry in the axial couplings and magnetic moments of baryons is analyzed in the $1/N_c$ expansion. A simple meson loop graph which is known to be of order $\sqrt{m_s}$ and leading order in $1/N_c$ correctly…
We consider flavor breaking in the the octet and decuplet baryon masses at second order in large-$N$ chiral perturbation theory, where $N$ is the number of QCD colors. We assume that $1/N \sim 1/N_F \sim m_s / \Lambda \gg m_{u,d}/\Lambda,…
Our recent works revisit the proof of chiral symmetry breaking in the confining phase of four-dimensional QCD-like theories, i.e. $SU(N_c)$ gauge theories with $N_f$ flavors of vectorlike quarks in the fundamental representation. The…
We determine the patterns of spontaneous symmetry breaking in strong-coupling lattice QCD in a fixed background baryon density. We employ a next-nearest-neighbor fermion formulation that possesses the SU(N_f)xSU(N_f) chiral symmetry of the…
The symmetry breaking pattern of QCD features two seemingly disconnected phenomena: the spontaneous breakdown of the Z(3) center symmetry in the deconfinement transition of pure-gauge QCD, and the spontaneous breaking of chiral…
We propose a symmetry breaking scheme for QCD with three massless quarks at high baryon density wherein the color and flavor SU(3)_color times SU(3)_L times SU(3)_R symmetries are broken down to the diagonal subgroup SU(3)_{color+L+R} by…
We critically reconsider the argument based on 't Hooft anomaly matching that aims at proving chiral symmetry breaking in confining four-dimensional QCD-like theories with $N_c>2$ colors and $N_f$ flavors. The main line of reasoning relies…
Over the past few years three dimensional Quantum Electrodynamics (QED$_3$) has attracted a lot of attention, because it may be an effective theory for the underdoped and non-superconducting region of the phase diagram of high $T_c$ cuprate…
While chiral symmetry breaking in the QCD vacuum is attributed to nonzero chiral condensate, an alternative symmetry breaking pattern with no chiral condensate is also possible, as pointed out by Stern. This hypothetical phase was excluded…
We present numerical results for non-compact three-dimensional QED for numbers of flavors N_f=1 and N_f=4.In particular, we address the issue of whether chiral symmetry is spontaneously broken in the continuum limit, and obtain a positive…
Non-compact QED(3) with four-component fermion flavor content larger than or equal to two is studied numerically near the chiral limit to understand its chiral symmetry breaking features. We monitor discretization and finite size effects on…
Recent interest in novel phases in high density QCD motivates the study of high density supersymmetric QCD (SQCD), where powerful exact results for supersymmetric gauge theories can be brought to bear in the strongly coupled regime. We…
The 1/N_c expansion provides a theoretical method for analyzing the spin-flavor symmetry properties of baryons in QCD that is quantitative, systematic and predictive. An exact spin-flavor symmetry exists for large-N_c baryons, whereas for…
We present new results on chiral symmetry breaking in nearly conformal gauge theories with fermions in the fundamental representation of the SU(3) color gauge group. The number of fermion flavors is varied in an extended range below the…
Common lore suggests that $N$-color QCD with massive quarks has no useful order parameters which can be non-trivial at zero baryon density. However, such order parameters do exist when there are $n_f$ quark flavors with a common mass and…
We propose a symmetry breaking scheme for QCD with three massless quarks at high baryon density wherein the color and flavor SU(3)_{color}xSU(3)_{L}xSU(3)_{R} symmetries are broken down to the diagonal subgroup SU(3)_{color+L+R} by the…
Non-compact three-dimensional QED is studied by computer simulations to understand its chiral symmetry breaking features for N_f>=2, on lattice volumes up to 50^3 and bare masses as low as ma=0.0000625. We compute the chiral condensate,…
We suggest that breaking of SU(3) flavor symmetry mainly resides in the baryon wave--functions while the charge operators have no (or only small) explicit symmetry breaking components. We utilize the collective coordinate approach to chiral…
We investigate the phase structure of Quantum Chromodynamics (QCD) in the vacuum as a function of quark flavor number $N_f$ within the chiral limit. By self-consistently solving the coupled DSEs for the quark and gluon propagators in a…
We use a variational procedure to study finite density QCD in an approximation in which the interaction between quarks is modelled by that induced by instantons. We find that uniform states with conventional chiral symmetry breaking have…