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Related papers: Lorentz and CPT Violating Chern-Simons Term in the…

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In this paper a Lorentz-violating CPT-even non-minimal coupling term is considered. A new interaction term between fermions and photons emerges. In this context, the differential cross-section for Bhabha scattering at finite temperature is…

High Energy Physics - Theory · Physics 2021-04-14 P. R. A. Souza , A. F. Santos , Faqir C. Khanna

Lorentz and CPT symmetries may be violated in new physics that emerges at very high energy scale, i.e., at the Planck scale. The differential cross section of the M\"oller scattering, due to Lorentz violation at finite temperature is…

High Energy Physics - Theory · Physics 2018-04-24 A. F. Santos , Faqir C. Khanna

In this paper we first discuss the analysis regarding the role of Lorentz symmetry in the perturbative non-gravitational anomalies for a family of fermions, which has been recently performed in arXiv:0809.0184. The theory is assumed to be…

High Energy Physics - Theory · Physics 2009-09-25 A. Salvio

The problem of Chern-Simons-like term induction via quantum corrections in four-dimensions is investigated in two different cases. In the first case, we consider two distinct approaches to deal with the exact fermion propagator of the…

High Energy Physics - Theory · Physics 2024-03-04 E. Passos , K. E. L. de farias , M. A. Anacleto , E. Maciel , C. A. G. Almeida

Small violation of Lorentz and CPT symmetries may emerge in models unifying gravity with other forces of nature. An extension of the standard model with all possible terms that violate Lorentz and CPT symmetries are included. Here a…

High Energy Physics - Theory · Physics 2019-03-27 P. R. A. Souza , A. F. Santos , S. C. Ulhoa , F. C. Khanna

An interacting theory that violates CPT invariance necessarily violates Lorentz invariance. On the other hand, CPT invariance is not sufficient for out-of-cone Lorentz invariance. Theories that violate CPT by having different particle and…

High Energy Physics - Phenomenology · Physics 2010-04-06 O. W. Greenberg

In this talk, I discuss some recent theoretical progress concerning the Lorentz- and CPT-violating extension of the standard model. The results summarized include the development of an explicit connection between noncommutative field theory…

High Energy Physics - Phenomenology · Physics 2009-11-10 Don Colladay

It is argued that the derivative expansion is a suitable method to deal with finite temperature field theory, if it is restricted to spatial derivatives only. Using this method, a simple and direct calculation is presented for the…

High Energy Physics - Theory · Physics 2009-11-07 L. L. Salcedo

In this work we analyse a non-minimal Lorentz-violating extension of the electroweak theory in the fermionic sector. Firstly we analyse the relation between the CKM rotation in the quark sector and possible contributions of this new…

High Energy Physics - Phenomenology · Physics 2020-04-22 Y. M. P. Gomes , J. A. Helayel-Neto

This talk at the CPT'25 meeting presents an overview of some recent results in Lorentz and CPT violation. Topics covered include the geometry of Finsler spaces associated with Lorentz violation, the resolution of the concordance problem in…

High Energy Physics - Phenomenology · Physics 2026-01-01 Alan Kostelecky

The fermionic f coefficient in the Lorentz-violating standard model extension presents a puzzle. Thus far, no observable quantity that depends upon f has ever been found. We show that this is because f is actually unnecessary. It has…

High Energy Physics - Theory · Physics 2009-11-11 B. Altschul

We study the $z=3$ Horava-Lifshitz QED with a CPT-breaking term, characterized by the axial vector $b_{\mu}$, and perform the one-loop calculations. Explicitly, we demonstrate that just as in the usual Lorentz-breaking QED, in our case, the…

High Energy Physics - Theory · Physics 2021-05-04 T. Mariz , R. Martinez , J. R. Nascimento , A. Yu. Petrov

In Lorentz violating quantum electrodynamics (QED) it is known that a radiatively induced Chern-Simons term appears in the effective action for the gauge field, which is finite but undetermined. This ambiguity is shown to be absent in a…

High Energy Physics - Theory · Physics 2012-08-22 Adolfo G. Grushin

We rediscuss the controversy on a possible Chern-Simons like term generated through radiative corrections in QED with a CPT violating term. We analyse some consequences of the division of the Lagrangian density between "free part" and…

High Energy Physics - Theory · Physics 2008-11-26 Guy Bonneau

We study the geometric optics limit of the electrodynamics in the presence of Lorentz violating Chern-Simons term in (3+1) dimensions. The Chern-Simons term couples the dual electromagnetic tensor to an external four-vector and the…

High Energy Physics - Phenomenology · Physics 2025-01-07 Arpan Das , Hriditi Howlader , Alekha C. Nayak

A modified Dirac equation with general Lorentz- and CPT-violating operators in the electromagnetic field is studied. Constraints on and possible sensitivities to Lorentz-violating coefficients in the nonminimal sector up to mass-dimension…

High Energy Physics - Phenomenology · Physics 2016-10-31 Yunhua Ding

This work tabulates measured and derived values of coefficients for Lorentz and CPT violation in the Standard-Model Extension. Summary tables are extracted listing maximal attained sensitivities in the matter, photon, neutrino, and gravity…

High Energy Physics - Phenomenology · Physics 2026-02-09 Alan Kostelecky , Neil Russell

The interpretation of neutrino oscillation data has led to the question whether, in principle, an antiparticle like antineutrino can have a different mass than its particle. In the framework of a Lorentz invariant CPT violation, which is…

High Energy Physics - Theory · Physics 2015-06-04 Masud Chaichian , Kazuo Fujikawa , Anca Tureanu

A general formalism is presented for violations of Lorentz and CPT symmetry in the neutrino sector. The effective hamiltonian for neutrino propagation in the presence of Lorentz and CPT violation is derived, and its properties are studied.…

High Energy Physics - Phenomenology · Physics 2009-09-25 Alan Kostelecky , Matthew Mewes

CPT and Lorentz violation in the photon sector is described within the minimal Standard-Model Extension by a dimension-3 Chern-Simons-like operator parametrized by a four-vector parameter $k_{AF}$ that has been very tightly bounded by…

High Energy Physics - Phenomenology · Physics 2017-11-13 D. Colladay , J. P. Noordmans , R. Potting