Lorentz Violating Julia-Toulouse Mechanism

We propose a new Lorentz invariant violating extension for the pure photonic sector of the Standard Model due to the condensation of topological defects in the context of the Julia-Toulouse mechanism. Possible physical consequences leading to direct measurable effects over the confining properties of the elementary particles are explored.Comment: 4 page

Aspects of finite electrodynamics in D=3 dimensions

We study the impact of a minimal length on physical observables for a three-dimensional axionic electrodynamics. Our calculation is done within the framework of the gauge-invariant, but path-dependent, variables formalism which is alternative to the Wilson loop approach. Our result shows that the interaction energy contains a regularised Bessel function and a linear confining potential. This calculation involves no theta expansion at all. Once again, the present analysis displays the key role played by the new quantum of length.Comment: 12 pages, 2 figures; reference list updated and extended; new aknowlegments; removed line after eq.(1) erroneously inserte

Remarks on Screening in a Gauge-Invariant Formalism

In this paper we display a direct and physically attractive derivation of the screening contribution to the interaction potential in the Chiral Schwinger model and generalized Maxwell-Chern-Simons gauge theory. It is shown that these results emerge naturally when a correct separation between gauge-invariant and gauge degrees of freedom is made. Explicit expressions for gauge-invariant fields are found.Comment: 13 pages, 1 figure, to appear in PR

Properties of noncommutative axionic electrodynamics

Using the gauge-invariant but path-dependent variables formalism, we compute the static quantum potential for noncommutative axionic electrodynamics, and find a radically different result than the corresponding commutative case. We explicitly show that the static potential profile is analogous to that encountered in both non-Abelian axionic electrodynamics and in Yang-Mills theory with spontaneous symmetry breaking of scale symmetry.Comment: 4 pages. To appear in PR

New forms of BRST symmetry in rigid rotor

We derive the different forms of BRST symmetry by using the Batalin-Fradkin-Vilkovisky formalism in a rigid rotor. The so called "dual-BRST" symmetry is obtained from usual BRST symmetry by making a canonical transformation in the ghost sector. On the other hand, a canonical transformation in the sector involving Lagrange multiplier and its corresponding momentum leads to a new form of BRST as well as dual-BRST symmetry.Comment: 10 Pages, revtex, No Fig

Standstill Electric Charge Generates Magnetostatic Field Under Born-Infeld Electrodynamics

The Abelian Born-Infeld classical non-linear electrodynamic has been used to investigate the electric and magnetostatic fields generated by a point-like electrical charge at rest in an inertial frame. The results show a rich internal structure for the charge. Analytical solutions have also been found. Such findings have been interpreted in terms of vacuum polarization and magnetic-like charges produced by the very high strengths of the electric field considered. Apparently non-linearity is to be accounted for the emergence of an anomalous magnetostatic field suggesting a possible connection to that created by a magnetic dipole composed of two mognetic charges with opposite signals. Consistently in situations where the Born-Infeld field strength parameter is free to become infinite, Maxwell`s regime takes over, the magnetic sector vanishes and the electric field assumes a Coulomb behavior with no trace of a magnetic component. The connection to other monopole solutions, like Dirac`s, t' Hooft`s or Poliakov`s types, are also discussed. Finally some speculative remarks are presented in an attempt to explain such fields.Comment: 11 pages, 3 figures. In this version is update a permanent address of the author L.P.G. De Assis and information on submission publication. Submetted to International Journal of Theoretical Physic

Solutions for f(R) gravity coupled with electromagnetic field

In the presence of external, linear / nonlinear electromagnetic fields we integrate f(R) \sim R+2{\alpha}\surd(R+const.) gravity equations. In contrast to their Einsteinian cousins the obtained black holes are non-asymptotically flat with a deficit angle. In proper limits we obtain from our general solution the global monopole solution in f(R) gravity. The scale symmetry breaking term adopted as the nonlinear electromagnetic source adjusts the sign of the mass of the resulting black hole to be physical.Comment: 7 pages no figure, final version for publication in European Physical Journal

Magnetized AdS/BCFT Correspondence in Horndeski Gravity

This work presents an investigation of the thermodynamics and hydrodynamics of a five-dimensional black hole in the presence of an external magnetic field. The solution is the gravity dual to an Anti-de-Sitter/Boundary Conformal Field Theory (AdS/BCFT) correspondence. For this, we will establish the AdS$_{5}$/BCFT$_{4}$ correspondence, and with it, we will study the properties of an anisotropic fluid with an external magnetic field. Using holographic renormalization we compute the free energy and holographic stress tensor residing on boundary Q. From the point of view of the fluid/gravity correspondence, we have a class of boundary extensions existing in boundary Q, for which the stress-energy tensor describes a magnetizing conformal fluid. We discuss the characteristics of this special solution, as well as its thermodynamic properties, for example, the null trace indicates that the bulk viscosity must be zero, which gives us a plasma without viscosity.Comment: 39 pages, 23 figures. arXiv admin note: text overlap with arXiv:2301.0312