Related papers: Studying the behavior of the strong interaction co…
Quantum Chromodynamics (QCD), the gauge field theory of the Strong Interaction, has specific features, asymptotic freedom and confinement, which determine the behaviour of quarks and gluons in particle reactions at high and at low energy…
The asymptotical behaviour of the QCD coupling strength is considered. Its upper bound is found from the present experimental data. The assumption about the finite asymptotical value of the coupling strength leads to the energy scale where…
The energies of a pair of strongly-interacting subsystems with arbitrary noninteger charges are examined from closed and open system perspectives. An ensemble representation of the charge dependence is derived, valid at all interaction…
We present a one-loop calculation of a gauge invariant QCD beta function. Using both momentum and temperature renormalization group equations we investigate the running coupling in the magnetic sector as a function of temperature and…
We show that the interaction constant governing the long-range electron-electron interaction in a quantum wire coupled to two reservoirs and capacitively coupled to a gate can be determined by a low frequency measurement. We present a…
The compatibility of theoretically calculated values for the strong coupling constant,through the renormalization group approach with experimental data is studied. There exist considerable divergence in-between theoretical and experimental…
In this work, a way starting from beta function is presented for obtaining well-defined coupling constant in UV and IR region. In the approach presented here, obvious singularity is removed, and asymptotic behaviour is reserved fully and…
In this paper, we systematically study the effective action for non-commutative QED in the static limit at high temperature. When $\theta p^{2}\ll 1$, where $\theta$ represents the magnitude of the parameter for non-commutativity and $p$…
Recently we have shown that a phase transition occurs in the leading and sub-leading approximation of the large N limit in rigid strings coupled to long range Kalb-Ramond interactions. The disordered phase is essentially the…
According to the present understanding, the observed diversity of the strong interaction phenomena is described by Quantum Chromodynamics, a gauge field theory with only very few parameters. One of the fundamental questions in this context…
A hierarchy of effective field theories is used to separate the contributions from different momentum scales and to calculate the free energy of QCD at high temperature in powers of the coupling constant up to order $g^5$. The behavior of…
An explicit model for the proton structure function interpolating between low- (VMD and Regge behavior)and high-$Q^2$ (GLAP evolution) is suggested. The model is fitted to the experimental data in a wide range of the kinematical variables…
The present knowledge on the strong coupling is briefly summarized. The most precise determinations of alpha_s, at different energies, are reviewed and compared at the Z mass scale, using the predicted QCD running. The impressive agreement…
The theory of strong interactions, QCD, is described in terms of a few parameters, namely the strong coupling constant alpha_s and the quark masses. We show how these parameters can be determined reliably using computer simulations of QCD…
The properties of the new analytic running coupling are investigated at the higher loop levels. The expression for this invariant charge, independent of the normalization point, is obtained by invoking the asymptotic freedom condition. It…
A mass scale $\mu_c$ representing the boundary between effective theories of strong interactions and perturbative QCD (infrared and ultraviolet regimes) exists when the $\beta$-function is characterized by a simple pole. This behaviour,…
The energy range and quality of strong-interaction data from recent years demand the study of higher orders in perturbative QCD, and of nonperturbative effects. I discuss a selection of recent progress in the theory of QCD at high energy,…
It has been proposed that the energy evolution of QCD amplitudes in the high-energy regime falls in the universality class of reaction-diffusion processes. We review the arguments for this correspondence, and we explain how it enables one…
The exchange energy, i.e. the splitting $\Delta E$ between gerade and ungerade states in the hydrogen molecule has proven very difficult in numerical calculation at large internuclear distances $R$, while known results are sparse and highly…
Sequences of experimental ground-state energies are mapped onto concave patterns cured from convexities due to pairing and/or shell effects. The same patterns, completed by a list of excitation energies, can be used to give numerical…