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T. Mariz

Publications and source records attributed to T. Mariz.

At least 55 records · Page 3Linked to original sources

On the Adler-Bell-Jackiw anomaly in a Horava-Lifshitz-like QED

We show the absence of the ABJ anomaly for the Horava-Lifshitz-like QED with any even $z$. Besides of this, we study the graph contributing to the ABJ anomaly at non-zero temperature and extend the Fujikawa's methodology of studying the integral measure for our model.

hep-th↗

On one-loop corrections in the Horava-Lifshitz-like QED

We study the one-loop two point functions of the gauge, scalar and spinor fields for a Horava-Lifshitz-like QED with critical exponent $z=2$. It turns out that, in certain cases, the dynamical restoration of the Lorentz symmetry at low energies can take place. We also analyze the three point vertex function of the gauge and spinor fields and prove that the triangle anomaly identically vanishes in this theory.

hep-th↗

On the decoupling of heavy states in higher-derivative supersymmetric field theories

We study the problem of decoupling of heavy chiral superfields in four-dimensional $N=1$ supersymmetric field theories with Lorentz-invariant and Lorentz-violating higher-derivative terms. We demonstrate that the earlier found effect of large logarithmic quantum corrections, due to heavy chiral superfields, takes place not only if the theory possesses quantum divergences, but also for essentially finite theories involving higher derivative terms, both Lorentz-invariant and Lorentz-breaking ones.

hep-th↗

Radiatively induced CPT-odd Chern-Simons term in massless QED

In this work, we study the radiative generation of the CPT-odd Lorentz-violating Chern-Simons term, arising from massless fermions. For this, we calculate the vacuum polarization tensor using the 't Hooft-Veltman regularization scheme, in which the result obtained for the coefficient of the Chern-Simons term is $(k_{AF})_μ=-\frac{e^2}{4π^2}\,b_μ$. This result leads us precisely to the same conductivity found in Weyl semimetals, i.e., the 't Hooft-Veltman regularization scheme is the correct one to be used in this context. We also discuss the temperature dependence of $(k_{AF})_μ$, in which at high temperature, $(k_{AF})_0\to0$ and $(k_{AF})_i\to-\frac{e^2}{4π^2}b_i$. In the context of Weyl semimetals, these results are in accordance with the fact that the chiral magnetic current $j^α=(k_{AF})_0ε^{0αλρ}\partial_λA_ρ$ vanishes at high temperature, whereas the anomalous Hall current $j^α=(k_{AF})_iε^{iαλρ}\partial_λA_ρ$ remains unaffected by the finite temperature.

hep-th↗

Lorentz-violating Euler-Heisenberg effective action

In this work, we study the radiative generation of the Lorentz-violating Euler-Heisenberg action, in the weak field approximation. For this, we first consider a nonperturbative calculation in the coefficient $c_{μν}$, however, by assuming rotational invariance. Within this approach, we also obtain the results of the amplitude for the photon triple splitting. In the following, we take into account the perturbative approach, where $c_{μν}$ is treated as a insertion in the propagator and a new vertex. The partial results are in fact an expansion up to first order in $c_{μν}$ of the nonperturbative ones, with $c_{00}=κ$ and $c_{0i}=c_{ij}=0$. This suggest that the complete results obtained in the nonperturbative approach can be used in both treatments.

hep-ph↗

Induced Lorentz-violating terms at finite temperature

We study the radiatively induced Lorentz-violating terms at finite temperature, namely, the higher-derivative term and the Chern-Simons term. These terms are induced by integrating out the fermions coupled to the coefficient $g^{κμν}$. The calculation of the resulting expressions is performed by using the derivative expansion and the Matsubara formalism. The Chern-Simons terms is nonzero only at finite temperature, whereas the higher-derivative term is finite at zero temperature, however, it goes to zero as the temperature grows to infinity. We also obtain a higher-derivative Chern-Simons term, nevertheless, it vanishes asymptotically.

hep-th↗

On the perturbative generation of the higher-derivative Lorentz-breaking terms

In this paper, we describe the perturbative generation of the higher-derivative Lorentz-breaking terms for the gauge field, that is, the Myers-Pospelov term and the higher-derivative Carroll-Field-Jackiw term. These terms are explicitly calculated in the one-loop approximation and shown to be finite and ambiguous.

hep-th↗

Radiatively induced Lorentz-violating operator of mass dimension five in QED

The first higher derivative term of the photon sector of Lorentz-violating QED, with operator of mass dimension $d=5$, is radiatively induced from the fermion sector, in which contains a derivative term with the dimensionless coefficient $g^{λμν}$. The calculation is performed perturbatively in the coefficient for Lorentz violation, and due to the fact that the contributions are quadratically divergent, we adopt dimensional regularization.

hep-th↗

Free energy of Lorentz-violating QED at high temperature

In this paper we study the one- and two-loop contribution to the free energy in QED with the Lorentz symmetry breaking introduced via constant CPT-even Lorentz-breaking parameters at the high temperature limit. We find the impact of the Lorentz-violating term for the free energy and carry out a numerical estimation for the Lorentz-breaking parameter.

hep-th↗

Slavnov-Taylor identities for noncommutative QED$_4$

In this work we present an analysis of the one-loop Slavnov-Taylor identities in noncommutative QED$_4$. The vectorial fermion-photon and the triple photon vertex functions were studied, with the conclusion that no anomalies arise.

hep-th↗

The Gödel solution in the modified gravity

We consider the modified gravity whose action represents itself as a sum of the usual Einstein-Hilbert action and the gravitational Chern-Simons term and show that the Gödel metric solves the modified equations of motion, thus proving that the closed timelike curves whose presence is characteristic for the Gödel solution are not forbidden in the case of the Chern-Simons modified gravity as well.

hep-th↗

Dynamical Lorentz symmetry breaking in 3D and charge fractionalization

We analyze the breaking of Lorentz invariance in a 3D model of fermion fields self-coupled through four-fermion interactions. The low-energy limit of the theory contains various sub-models which are similar to those used in the study of the graphene or in the description of irrational charge fractionalization.

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