Renormalized Electron Mass in Nonrelativistic QED

Within the framework of nonrelativistic QED, we prove that, for small values of the coupling constant, the energy function, ${E_{\vec{P}}}Within the framework of nonrelativistic QED, we prove that, for small values of the coupling constant, the energy function, E_[(P)\vec]{E_{\vec{P}}}, of a dressed electron is twice differentiable in the momentum [(P)\vec]{\vec{P}} in a neighborhood of [(P)\vec]=0{\vec{P}=0}. Furthermore, \frac?²E_[(P)\vec](?|[(P)\vec]|)²{\frac{\partial^2E_{\vec{P}}}{(\partial |\vec{P}|)^2}} is bounded from below by a constant larger than zero. Our results are proven with the help of iterative analytic perturbation theory.     

Complex Langevin solution to an effective theory of compact lattice QED

By means of a complex Langevin algorithm, we simulate an effective three-dimensional lattice theory which arises from compact lattice QED at finite temperature and finite chemical potential. The complex process coverges remarkably well.     

Particles inside electrolytes with ion-specific interactions,their effective charge distributions,and effective interactions

In this work, we explore the statistical physics of colloidal particles that interact with electrolytes via ion-specific interactions. Firstly we study particles interacting weakly with electrolyte using linear response theory. We find that the mean potential around a particle is linearly determined by the effective charge distribution of the particle, which depends both on the bare charge distribution and on ion-specific interactions. We also discuss the effective interaction between two such particles and show that, in the far field regime, it is bilinear in the effective charge distributions of two particles. We subsequently generalize the above results to the more complicated case where particles interact strongly with the electrolyte.Our results indicate that in order to understand the statistical physics of non-dilute electrolytes, both ion-specific interactions and ionic correlations have to be addressed in a single unified and consistent framework.     

G-essence with Yukawa interactions

We study the g-essence model with Yukawa interactions between a scalar field φ and a Dirac field ψ. For the homogeneous, isotropic and flat Friedmann–Robertson–Walker universe filled with the such g-essence, the exact solution of the model is found. Moreover, we reconstruct the corresponding scalar and fermionic potentials which describe the coupled dynamics of the scalar and fermionic fields. It is shown that some particular g-essence models with Yukawa interactions correspond to the usual and generalized Chaplygin gas unified models of dark energy and dark matter. Also we present some scalar–fermionic Dirac–Born–Infeld models corresponding g-essence models with Yukawa interactions which again describe the unified dark energy–dark matter system.     

Forbidden band width and effective charge in crystal lattice of ZnS

The optical and thermal widths of the forbidden band are determined by the absorption spectrum and temperature dependence of the conductivity respectively. The difference between them is determined also by the spectral sensitivity of different phosphors to optical stimulation. The effective charge of an ion in ZnS is determined in several ways by using the value of this difference, the refractive index, dielectric constant and frequencies in the Raman spectrum and the spectrum of infra-red absorption of ZnS. It was found to be equal to approximately half of the electron charge.     

Non-renormalizable Yukawa interactions and Higgs physics

We explore a scenario in the Standard Model in which dimension-four Yukawa couplings are forbidden by a symmetry, and the Yukawa interactions are dominated by effective dimension-six interactions. In this case, the Higgs interactions to the fermions are enhanced in a large way, whereas its interaction with the gauge bosons remains the same as in the Standard Model. In hadron colliders, Higgs boson production via gluon-gluon fusion increases by a factor of nine. Higgs decay widths to fermion-antifermion pairs also increase by the same factor, whereas the decay widths to photon-photon and γZ are reduced. Current Tevatron exclusion range for the Higgs mass increases to ∼146-222 GeV in our scenario, and new physics must appear at a scale below a TeV.     

The nuclear Yukawa model on a lattice

We present the results of the quantum field theory approach to the nuclear Yukawa model obtained by standard lattice techniques. We have considered the simplest case of two identical fermions interacting via a scalar meson exchange. Calculations have been performed using Wilson fermions in the quenched approximation. We found the existence of a critical coupling constant above which the model cannot be numerically solved. The range of the accessible coupling constants is below the threshold value for producing two-body bound states. Two-body scattering lengths have been obtained and compared to the non-relativistic results.     

Charge polarization in compact lattice QED

We investigate the polarization cloud around static electric charges in the framework of compact lattice QED. We calculate the correlations of Polyakov loops with the electric charge densityψ ^? ψ normalized to the chiral condensate. It turns out that virtual anticharges screen static charges as expected from continuum QED. Charge polarization is more pronounced at strong couplings and extends to a longer range on the lattice in the weak coupling phase. In both phases the correlations decrease with larger fermion mass.     

Baryon-Baryon interactions from lattice QCD

We report on new attempt to investigate baryon-baryon interactions in lattice QCD.From the Bethe-Salpeter （BS） wave function,we have successfully extracted the nucleon-nucleon （NN） potentials in quenched QCD simulations,which reproduce qualitative features of modern NN potentials.The method has been extended to obtain the tensor potential as well as the central potential and also applied to the hyperonnucleon （YN） interactions,in both quenched and full QCD.     

Baryon-Baryon interactions from lattice QCD

We report on new attempt to investigate baryon-baryon interactions in lattice QCD. From the Bethe-Salpeter (BS) wave function, we have successfully extracted the nucleon-nucleon (NN) potentials in quenched QCD simulations, which reproduce qualitative features of modern NN potentials. The method has been extended to obtain the tensor potential as well as the central potential and also applied to the hyperon-nucleon (YN) interactions, in both quenched and full QCD.     

A modest proposal for generating Yukawa couplings from gauge interactions

We propose that the quark and lepton Yukawa superpotential couplings to Higgs supermultiplets arise from non-perturbative gauge interactions. This is possible in models with an SU(N) × G gauge group. We present a three-generation model based on SU(8) × G, and indicate how such a scenario could lead to a realistic hierarchy of quark and lepton masses.     

Charge radii from lattice relative charge distributions

Electromagnetic charge radii values are extracted from relative charge distribution data for pseudoscalars using lattice QCD techniques. This is done with Wilson fermions and SU(2) color at five values of the hopping parameter.