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Related papers: Influence of Lorentz-violating terms on a two-leve…

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We study the impact of general disformal metric transformations on fermions, which shift the gravitational metric by an additional rank-2 tensor. This tensor can in principle be constructed from scalar-field gradients, vector fields, or…

High Energy Physics - Phenomenology · Physics 2025-10-10 Guillem Domènech , Apostolos Tsabodimos , Nathaniel Sherrill , Alexander Ganz , Fiona Kirk

We consider the problem of a qubit driven by a harmonically oscillating external field while it is coupled to a quantum two-level system. We perform a systematic numerical analysis of the problem by varying the relevant parameters. The…

Superconductivity · Physics 2007-05-23 S. Ashhab , J. R. Johansson , Franco Nori

We propose a CPT-even and Lorentz-violating dimension-five nonminimal coupling between fermionic and gauge fields, involving the CPT-even and Lorentz-violating gauge tensor of the Standard-Model Extension. This nonminimal coupling modifies…

High Energy Physics - Theory · Physics 2017-08-23 R. Casana , M. M. Ferreira , E. Passos F. E. P. Dos Santos , E. O. Silva

CPT-odd effects on the neutrino charge radius are studied within the Standard Model Extension. We consider CPT violation from the electroweak Yang-Mills sector, characterized by Lorentz-violating coefficients $(k_1)_\mu$ and $(k_2)_\mu$,…

High Energy Physics - Phenomenology · Physics 2025-08-21 Y. Flores-Orea , J. J. Toscano

A framework is presented for the factorization of high-energy hadronic processes in the presence of Lorentz and CPT violation. The comprehensive effective field theory describing Lorentz and CPT violation, the Standard-Model Extension, is…

High Energy Physics - Phenomenology · Physics 2020-05-19 Alan Kostelecky , Enrico Lunghi , Nathan Sherrill , A. R. Vieira

The effective-Lagrangian description of Lorentz-invariance violation provided by the so-called Standard-Model Extension covers all the sectors of the Standard Model, allowing for model-independent studies of high-energy phenomena that might…

High Energy Physics - Phenomenology · Physics 2021-03-10 J. Alfonso Ahuatzi-Avendaño , Javier Montaño , Héctor Novales-Sánchez , Mónica Salinas , J. Jesús Toscano

We consider the gravitational effects of a single, fixed-norm, Lorentz-violating timelike vector field. In a cosmological background, such a vector field acts to rescale the effective value of Newton's constant. The energy density of this…

High Energy Physics - Theory · Physics 2010-04-06 Sean M. Carroll , Eugene A. Lim

Assuming that CPT is violated in the neutrino sector seems to be a viable alternative to sterile neutrinos when it comes to reconciling the LSND anomaly with the remainder of the neutrino data. There are different (distinguishable) ways of…

High Energy Physics - Phenomenology · Physics 2009-11-07 Andre de Gouvea

Neutrinos allow for a test of the hypothesis that the fermions of the Standard Model have Fermi-point splitting, analogous to the fermionic quasi-particles of certain condensed-matter systems. If present, the corresponding Lorentz-violating…

High Energy Physics - Phenomenology · Physics 2007-05-23 F. R. Klinkhamer

We investigate an alternative CPT-odd Lorentz-breaking QED which includes the Carroll-Field-Jackiw (CFJ) term of the Standard Model Extension (SME), writing the gauge sector in the action in a Palatini-like form, in which the vectorial…

High Energy Physics - Theory · Physics 2019-09-12 J. C. C. Felipe , H. G. Fargnoli , A. P. Baeta Scarpelli , L. C. T. Brito

The detectability of the fermion-potentials appearing in a unified model of fermions is discussed from the viewpoint of an effective field theory. Although the fermion-potentials are effectively represented as terms similar to the…

General Physics · Physics 2013-02-21 Kimihide Nishimura

We consider renormalizable Standard-Model extensions that violate Lorentz symmetry at high energies, but preserve CPT, and do not contain elementary scalar fields. A Nambu--Jona-Lasinio mechanism gives masses to fermions and gauge bosons,…

High Energy Physics - Phenomenology · Physics 2011-03-21 Damiano Anselmi , Emilio Ciuffoli

This work sets out to compute the corrections to the Euler-Heisenberg effective action that arise from spacetime-dependent background anisotropies that violate Lorentz symmetry. To accomplish our task, we evaluate the functional determinant…

High Energy Physics - Theory · Physics 2026-03-24 Wagno Cesar e Silva , João Paulo S. Melo , José A. Helayël-Neto

We discuss situations under which Lorentz symmetry is violated in effective gravitational field theories that arise in the low-energy limit of strings. In particular, we discuss spontaneous violation of the symmetry by the ground state of…

High Energy Physics - Theory · Physics 2022-05-17 Nick E. Mavromatos

We derive a modified dispersion relation (MDR) in the Lorentz violation extension of quantum electrodynamics (QED) sector in the standard model extension (SME) framework. Based on the extended Dirac equation and corresponding MDR, we…

High Energy Physics - Phenomenology · Physics 2010-10-27 Zhi Xiao , Bo-Qiang Ma

Some solutions to the anomalies of ultra high energy cosmic-ray(UHECR) and TeV $\gamma$-rays require disturbed non-quadratic dispersion relations, which suggest the Lorentz violation. Also, some new theories such as quantum gravity, string…

General Physics · Physics 2007-08-14 Ying-Qiu Gu

We consider the role of Lorentz symmetry in noncommutative field theory. We find that a Lorentz-violating standard-model extension involving ordinary fields is general enough to include any realisitc noncommutative field theory as a subset.…

High Energy Physics - Phenomenology · Physics 2017-08-23 Charles D. Lane

Spontaneous Lorentz violation is a viable mechanism to look for Planck scale physics. In this work, we study spontaneous Lorentz violation models, in flat spacetime, where a vector field produces such a violation and matter is modeled by a…

High Energy Physics - Theory · Physics 2016-01-26 Yuri Bonder , Carlos A. Escobar

We have investigated the perturbative ambiguity of the radiatively induced Chern-Simons term in differential regularization. The result obtained in this method contains all those obtained in other regularization schemes and the ambiguity is…

High Energy Physics - Theory · Physics 2009-10-31 W. F. Chen

The recent direct detection of gravitational waves reported by Advanced LIGO has inspired the current article. In this context, a particular Lorentz-violating framework for classical, massive particles is the focus. The latter is…

General Relativity and Quantum Cosmology · Physics 2017-09-12 M. Schreck