相关论文: Relativistic theory of string breaking in QCD

A model for SU(n) string breaking on the lattice is formulated using strong coupling ideas. Although necessarily rather crude, the model gives an explicit picture of string breaking in the presence of dynamical quarks as a mixing phenomenon…

We present a chiral constituent quark model for light and strange baryons providing a unified description of their ground states and excitation spectra. The model relies on constituent quarks and Goldstone bosons arising as effective…

A semiclassical picture of spontaneous symmetry breaking in light front field theory is formulated. It is based on a finite-volume quantization of self-interacting scalar fields obeying antiperiodic boundary conditions. This choice avoids a…

Four-dimensional string theories predict in general the existence of light exotic particles with fractional electric charges. Such particles could escape present observations if they are confined by a gauge group of the "hidden" sector into…

The main goal of this work is to pursue an investigation of cosmic string configurations focusing on possible consequences of the Lorentz-symmetry breaking by a background vector. We analyze the possibility of cosmic strings as a viable…

We have been examining the phenomenon of string breaking in QCD with two flavors of dynamical staggered quarks. We construct a transfer matrix from a combination of ``string'' and ``two-meson'' channels. Preliminary results with low…

We present new results for the SU(3) "sextet model" with two flavors transforming according to the two-index symmetric representation of the gauge group. The simulations are performed using unimproved Wilson fermions. We measure the meson…

We study the potential of a static quark anti-quark pair in the confinement ``phase'' of the SU(2) Higgs model. Around separation r_b, the confining string of the gauge field breaks by formation of a dynamical pair of light quarks. The…

This series of three lectures covers (a) a basic introduction to symmetry breaking in general and chiral symmetry breaking in QCD, (b) an overview of the present status of lattice data and the knowlegde that we have at finite temperature…

It is shown that the principal pattern in baryon spectroscopy, which is associated with the flavor-spin dependent hyperfine interaction, is due to the spontaneous breaking of chiral symmetry in QCD and persists in the chiral limit. All…

Spontaneous particle-pair formation is a fundamental phenomenon in nature. It can, for example, appear when the potential energy between two particles increases with separation, as if they were connected by a tense string. Beyond a critical…

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 investigate the effect of a constant external non-Abelian field on chiral symmetry breaking in a (2+1)-dimensional Nambu-Jona-Lasinio model and in 3D QCD by solving the gap equation and the Bethe-Salpeter equation, and also by RG…

Using lattice QCD we study the spectrum of low-lying fermion eigenmodes. According to the Banks-Casher relation, accumulation of the low-mode is responsible for the spontaneous breaking of chiral symmetry in the QCD vacuum. On the lattice…

We demonstrate that the chiral gauge flavor $SU(3)_f$ dynamics spontaneously generates the chiral symmetry breaking fermion self energies $\Sigma(p^2)$ resulting in wide and wild spectra of lepton and quark masses. The Goldstone theorem…

Beyond the spontaneous chiral symmetry breaking scale light and strange baryons should be considered as systems of three constituent quarks with an effective confining interaction and a flavor-spin chiral interaction that is mediated by the…

An implication of the spontaneous chiral symmetry breaking in QCD is that at low energy and resolution there appear quasiparticles - constituent quarks and Goldstone bosons. Thus, light and strange baryons should be considered as systems of…

The static potential $V(r)$ between a static quark and a static antiquark separated by a distance r is defined as the energy of the ground state of the system. As a consequence of confinement, the energy between the quark-antiquark pair is…

'Constituent quarks' means massive quarks, in contrast to the nearly massless u,d,s quarks of the QCD lagrangian. The dynamical or constituent masses appear owing to the spontaneous chiral symmetry breaking in QCD. A realistic mechanism of…

The quantum properties of a helix-like shaped QCD string are studied in the context of the semi-classical Lund fragmentation model. It is shown how simple quantization rules combined with the causality considerations in the string…