Related papers: Extending the Standard Model to Include CPT- and L…
Stability and causality are investigated for quantum field theories incorporating Lorentz and CPT violation. Explicit calculations in the quadratic sector of a general renormalizable lagrangian for a massive fermion reveal that no…
The effects of Lorentz and CPT violations on macroscopic objects are explored. Effective composite coefficients for Lorentz violation are derived in terms of coefficients for electrons, protons, and neutrons in the Standard-Model Extension,…
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…
Apparent violations of CPT and Lorentz symmetry might arise in nature as a result of spontaneous symmetry breaking in a theory beyond the standard model. This talk summarizes a few relevant theoretical and experimental issues, with some…
If Lorentz symmetry is violated at high energies, interactions that are usually non-renormalizable can become renormalizable by weighted power counting. Recently, a CPT invariant, Lorentz violating extension of the Standard Model containing…
Tests of CPT and Lorentz symmetry using neutral-meson oscillations are studied within a formalism that allows for indirect CPT and T violation of arbitrary size and is independent of phase conventions. The analysis is particularly…
The breakdown of spacetime symmetries has recently been identified as a promising candidate signal for underlying physics, possibly arising through quantum-gravitational effects. This talk gives an overview over various aspects of CPT- and…
Minuscule violations of CPT and Lorentz invariance might arise in an extension of the standard model as suppressed effects from a more fundamental theory. In this contribution to the CarruthersFest, I present and answer some questions about…
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…
A general Lorentz-violating extension of the standard model of particle physics, allowing for both CPT-even and CPT-odd effects, is described. Some of its theoretical aspects and experimental implications are summarized.
In this work, we analyze a gravity model with higher derivatives including a CPT-even Lorentz-violating term. In principle, the model could be a low-energy limit of a Lorentz-invariant theory presenting the violation of Lorentz symmetry as…
Lorentz violation has been a popular field in recent years in the search for new physics beyond the Standard Model. We present a general method to build all Lorentz-violating terms in gauge field theories, including ones involving operators…
This talk discusses theoretical aspects of tests of CPT and Lorentz Symmetry that will in principle be possible with trapped antihydrogen. The framework is the standard-model extension, which admits minuscule violations of CPT and Lorentz…
Broken spacetime symmetries might emerge from a fundamental physical theory. The effective low-energy theory might be expected to exhibit violations of supersymmetry and Lorentz invariance. Some illustrative models which combine…
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,…
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.…
Overview of spontaneous Lorentz and CPT breaking mechanism in the context of the standard model contributed to the proceedings for the Coral Gables meeting.
I review first some theoretical motivations for violation of Lorentz and/or CPT Invariance. Although the latter symmetries may be violated in a quantum gravity setting, nevertheless there are situations in which these violations are due to…
A review is presented of some recent Lorentz and CPT tests in atomic and particle systems where the predominant interactions are described by quantum electrodynamics. A theoretical framework extending QED in the context of the standard…
The gauge-invariant Chern-Simons-type Lorentz- and CPT-breaking term is here re-assessed and issues like causality, unitarity, spontaneous gauge-symmetry breaking are investigated. Moreover, we obtain a minimal extension of such a system to…