Related papers: String Breaking in Quenched QCD
We argue that broken-symmetry states with either spatially diagonal or spatially off-diagonal order are likely in the quantum Hall regime, for clean multiple quantum well (MQW) systems with small layer separations. We find that for MQW…
Metastable cosmic strings appear in models of new physics with a two-step symmetry breaking $G\to H\to 1$, where $\pi_1(H)\neq 0$ and $\pi_1(G)=0$. They decay via the monopole-antimonopole pair creation inside. Conventionally, the breaking…
We study the change in free and internal energy due to the presence of a heavy quark anti-quark pair in a thermal heat bath in QCD with 2-flavors of staggered quarks at finite temperature. We discuss string breaking below as well as…
We present preliminary results for the mass spectrum of the nucleon and its low-lying excited states from quenched lattice QCD using the domain wall fermion method which preserves the chiral symmetry at finite lattice cutoff. Definite mass…
We have studied the light hadron spectrum and decay constants for quenched QCD at beta=6.2 on a 24^3x48 lattice. We compare the results obtained using a nearest-neighbour O(a)-improved ("clover") fermion action with those obtained using the…
We present the results of a systematic, first-principles study of the spectrum and decay constants of mesons for different numbers of color charges N, via lattice computations. We restrict our attention to states in the non-zero isospin…
I quickly review the successes of quantum chromodynamics. Then I assess the current state of the electroweak theory, making brief comments about the search for the Higgs boson and some of the open issues for the theory. I sketch the…
A generalized linear sigma model is employed to study the quark structure of low lying scalar as well as pseudoscalar states. The model allows the possible mixing of quark anti-quark states with others made of two quarks and two antiquarks…
We investigate the possible ground states of QCD at asymptotic densities, where the theory is expected to exhibit color superconductivity. We characterize the color-flavor structure of possible diquark condensates, and find those that are…
We present the perturbative and non-perturbative QCD structure of the dipole-dipole scattering amplitude in momentum space. The perturbative contribution is described by two-gluon exchange and the non-perturbative contribution by the…
We study the color correlation between two static quarks in 3Q ($QQQ$) and 4Q ($QQ\bar Q\bar Q$) multiquark systems at $T=0$ based on the reduced two-body density matrices $\rho$ in color space. We perform quenched lattice QCD calculations…
We present a lattice investigation of heavy-light mesons in the quenched approximation, using non-relativistic QCD for the heavy quark and a clover improved Wilson formulation for the light quark. A comprehensive calculation of the…
We show that stable local cosmic strings are a generic prediction of supersymmetric models where supersymmetry is broken at scales within a few orders of magnitude of the weak scale and is fed down to the observable sector by gauge…
The effect of using smeared sink operators on the hadron spectrum is studied for quenched twisted mass lattice QCD with up, down, and strange quarks. Gaussian smearing is used for quark fields, and stout link smearing for gauge fields.…
We present new results on properties of $SU(2)$ QCD in lattice regularization. Our main goal is to find the transition line confinement - deconfinement in $\mu - T$ plane. We compute the Polyakov loop and the string tension to determine…
Hybrid quantum systems in the ultrastrong, and even more in the deep-strong, coupling regimes can exhibit exotic physical phenomena and promise new applications in quantum technologies. In these nonperturbative regimes, a qubit--resonator…
Evidence from the lattice suggests that formation of a flux tube between a $q\bar{q}$ pair in the QCD vacuum leads to quark confinement. For large separations between the quarks, it is conjectured that the flux tube has a behaviour similar…
We present our final results of the charmonium spectrum in quenched QCD on anisotropic lattices. Simulations are made with the plaquette gauge action and a tadpole improved clover quark action employing $\xi = a_s/a_t = 3$. We calculate the…
We apply the maximum entropy method to extract the spectral functions for pseudoscalar and vector mesons from hadron correlators previously calculated at four different lattice spacings in quenched QCD with the Wilson quark action. We…
The meson spectrum of QCD is studied in the framework of nonperturbative QCD as a function of varying quark masses $m_q$. It is shown, that the total spectrum consists of two branches: 1) the standard one, which may be called the flux-tube…