相关论文: Is Quantization of QCD Unique at the Non-Perturbat…
In second order perturbation theory different definitions are known of gauge invariant perturbations in single field inflationary models. Consequently the corresponding gauge invariant cubic actions do not have the same form. Here we show…
We argue that QCD belongs to a topologically ordered phase similar to many well-known condensed matter systems with a gap such as topological insulators or superconductors. Our arguments are based on an analysis of the so-called "deformed…
This work is the first check of gauge invariance for nonperturbative calculations in light-front QED. To quantize QED in an arbitrary covariant gauge, we use a light-front analog of the equal-time Stueckelberg quantization. Combined with a…
A new local, covariant and nilpotent symmetry is shown to exist for the interacting BRST invariant U(1) gauge theory in two dimensions of space-time. Under this new symmetry, it is the gauge-fixing term that remains invariant and the…
Some interesting nonperturbative properties of the strongly coupled 4D compact U(1) lattice gauge theories, both without and with matter fields, are pointed out. We demonstrate that the pure gauge theory has a non-Gaussian fixed point with…
We show that there are many candidates for the quintessence and/or the QCD axions in a class of chiral $U(1)$ gauge theories. Their qualities are high enough to serve as the dark energy and/or to solve the strong CP problem. Interestingly,…
The theory of the strong interactions, Quantum Chromodynamics (QCD), has been addressed by a variety of non-perturbative techniques over the decades since its introduction. We have investigated Hamiltonian formulations with different…
The system of light quark and heavy antiquark source is studied in 1+1 QCD in the large N_C limit. The situation is demonstrated to be the two dimensional analogue of the problem in 3+1 QCD corresponding to the essentially nonlocal case of…
Recent developments concerning canonical quantisation and gauge invariant quantum mechanical systems and quantum field theories are briefly discussed. On the one hand, it is shown how diffeomorphic covariant representations of the…
"Equivalent unconstrained systems" for QCD obtained by resolving the Gauss law are discussed. We show that the effects of hadronization, confinement, spontaneous chiral symmetry breaking and $\eta_0$-meson mass can be hidden in solutions of…
Pure gauge compact QED on hypercubic lattices is considered with periodically closed monopole currents suppressed. We compute observables on sublattices which are nested around the centre of the lattice in order to locate regions where…
We study 2-flavor Hamiltonian lattice QCD in (1+1)D with hardcore gluons, at zero and finite density, by means of matrix product states. We introduce a formulation of the theory where gauge redundancy is absent and construct a gauge…
Inspired by recent studies of high-scale decay constant or flavorful QCD axions, we review and clarify their existence in effective string models with anomalous $U(1)$ gauge groups. We find that such models, when coupled to charged scalars…
Stochastic quantization is applied to derivation of equations connecting multilocal gauge-invariant correlators in different field theories. They include Abelian Higgs Model, QCD with spinless quarks at T=0 and T>0 and QED, where spin…
The problem of gauge invariance in an ultraviolet complete quantum field theory (QFT) with nonlocal interactions is investigated. For local fields that couple through a nonlocal interaction, it is demonstrated that the quantum…
In the framework of superfield approach, we derive the local, covariant, continuous and nilpotent (anti-)BRST and (anti-)co-BRST symmetry transformations on the U(1) gauge field $(A_\mu)$ and the (anti-)ghost fields $((\bar C)C)$ of the…
Vacuum characteristics quantifying dynamical tendency toward self-duality in gauge theories could be used to judge the relevance of classical solutions or the viability of classically motivated vacuum models. Here we decompose the field…
We show that the assumption of non-zero topological susceptibility of the vacuum in a fermion-free version of a theory, such as gravity or QCD, suffices to conclude the following: Once N massless fermion flavors are added to the theory,…
Thermodynamic properties of the QCD nonperturbative vacuum with two light quarks are studied. It is shown that at low temperatures T<M_\pi relativistic massive pions can be treated within the dilute gas approximation. Analytic temperature…
The long standing problem of non perturbative renormalization of a gauge field theoretical Hamiltonian is addressed and explicitly carried out within an (effective) light-cone Hamiltonian approach to QCD. The procedure is in line with the…