Related papers: Effective Regge QCD
We compute the three-loop helicity amplitudes for $q\bar{q} \to gg$ and its crossed partonic channels, in massless QCD. Our analytical results provide a non-trivial check of the color quadrupole contribution to the infrared poles for…
Generalizations of QCD in which the number of colors N is taken to infinity are characterized by profound mathematical properties, with far-reaching implications for fundamental problems and for phenomenological issues alike. In this…
We briefly discuss the recent discovery of reducible contributions to QED effective actions due to the presence of external electromagnetic fields at tree level and higher loop-order. We classify the physical effects of these contributions…
On the basis of the results of a new renormalisation group improved small-x resummation scheme, we argue that the range of validity of perturbative calculations is considerably extended in rapidity with respect to leading log expectations.…
We consider a simple nonlinear (quartic in the fields) gauge-invariant modification of classical electrodynamics, which possesses a regularizing ability sufficient to make the field energy of a point charge finite. The model is exactly…
We analyze upper limits on a possible gluon mass, $m_g$. We first discuss various ways to modify quantum chromodynamics to include $m_g \ne 0$, including a bare mass, a Higgs mechanism, and dynamical breaking of color SU(3)$_c$. From an…
The normal phase of the high-$T_c$ cuprates is apparently not described by Fermi liquid theory. It has been proposed that a dynamically generated gauge field must appear in the effective field theory. Even a simple spinon-gauge system is…
Quantum gauge theories with finite-dimensional representation spaces are constructed that can have canonical gauge field theories as singular limits. They describe nature as a recursive quantum assembly by iterating Fermi-Dirac…
Recent findings on the spectrum of heavy-quark mesons from computer simulations of quarks and gluons in lattice QCD are summarized, with particular attention to quark-antiquark states bound by an excited gluon field. The validity of a…
The study of gluon radiation in QCD, in the limit of small ("soft") momentum, remains an active research area, with a variety of phenomenological and theoretical applications. Soft gluon emission leads to large logarithms in perturbation…
We calculate the low-energy limit of heavy quark current correlators within an expansion in the inverse heavy quark mass. The induced low-energy currents built from the gluon fields corresponding to the initial heavy quark currents are…
We use a QCD relativistic potential model to compute the strong coupling constant $g$ appearing in the effective Lagrangian which describes the interaction of $0^-$ and $1^-$ $\bar q Q$ states with soft pions in the limit $m_Q \to \infty$.…
The purpose of this article is twofold. First, we attempt to give a brief overview of the different application areas of quantum electrodynamics (QED). These include fundamental physics (prediction of atomic energy levels), where the atom…
Quarkonium suppression is one of the most investigated probes of the medium produced in heavy-ion collisions. In this thesis we extend the well-established and successful zero temperature framework of Non-Relativistic (NR) Effective Field…
We provide the last missing ingredient necessary to approximate one-loop amplitudes in QCD with massive quarks in the limit of vanishing energy of a single gluon up to terms suppressed by this energy. Our main result is a soft operator…
Employing scalar QCD we study the gluon emission of heavy quarks created by the interaction with light quarks considered as dynamical scattering centers. We develop approximation formulas for the high energy limit and study when the full…
Halpern's field strength's formulation of gauge theories is applied to effective QED_3, namely, a gauge invariant theory for an Abelian gauge field $A_\mu$ with non-localities and self-interactions. The resulting description in terms of the…
I derive expressions for various correlators of the gauge field and find propagators in a new gauge A^\tau=0. This gauge is a part of the wedge form of relativistic dynamics suggested earlier as the tool for the study of quantum dynamics in…
The strong coupling limit (beta_gauge = 0) of QCD offers a number of remarkable research possibilities, of course at the price of large lattice artifacts. Here, we determine the complete phase diagram as a function of temperature T and…
We consider the large-$D$ limit of Einstein gravity. It is observed that a consistent leading large-$D$ graph limit exists, and that it is built up by a subclass of planar diagrams. The graphs in the effective field theory extension of…