Related papers: Threshold analyses and Lorentz violation
Momentum dependence of quantum corrections with higher-dimensional Lorentz violation is examined in electrodynamics on orbifolds. It is shown that effects of the Lorentz violation are not decoupled at high energy scales. Despite the loss of…
A more complete theoretical model of testing Lorentz violation by the comparison of atomic clocks is developed in the Robertson-Mansouri-Sexl kinematic framework. As this frame postulates the deviation of the coordinate transformation from…
Working in the context of a Lorentz-violating extension of the standard model we show that estimates of Lorentz symmetry violation extracted from ultra-high energy cosmic rays beyond the Greisen-Kuzmin-Zatsepin (GZK) cutoff allow for…
Regimes of Lorentz-violating effective field theories are studied in which departures from Lorentz symmetry are nonperturbative. Within a free toy theory exhibiting Lorentz breakdown involving an operator of mass dimension three, it is…
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.…
If Lorentz symmetry is broken, it must have occurred dynamically, via a vector or tensor field whose potential energy forces it to take on a non-zero background expectation value "in vacuum". If the set of minima of this potential (the…
Astroparticle physics has recently reached a new status of precision due to the construction of new observatories, operating innovative technologies and the detection of large numbers of events and sources. The precise measurements of…
Lorentz invariance, the fundamental symmetry of Einstein's theory of Special Relativity, has been established and tested by many classical and modern experiments. However, many theories that unify the Standard Model of particle physics and…
One possible feature of quantum gravity may be the violation of Lorentz invariance. In this paper we consider one particular manifestation of the violation of Lorentz invariance, namely modified dispersion relations for massive neutrinos.…
Existing experimental data for neutrino oscillations are consistent with Lorentz-violating massless neutrinos. This talk summarizes some aspects of neutrino oscillations from the perspective of Lorentz and CPT violation in effective quantum…
A relativistic theory for neutrino superluminality is presented (in principle, the same mechanism applies also to other fermions). The theory involves the standard-model particles and one additional heavy sterile neutrino with an…
A hypothetical violation of Lorentz invariance in the electrons' equation of motion (expressed within the Lorentz-violating extension of the standard model) leads to a change of the geometry of crystals and thus shifts the resonance…
The Lorentz-violating isotropic modified Maxwell theory minimally coupled to standard Dirac theory is characterized by a single real dimensionless parameter which is taken to vanish for the case of the standard (Lorentz-invariant) theory. A…
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…
In this letter we reconsider the role of Lorentz invariance in the dynamical generation of the observed internal symmetries. We argue that, generally, Lorentz invariance can only be imposed in the sense that all Lorentz non-invariant…
We motivate the concept of emergent gauge symmetry and discuss ways that this concept can be tested. The key idea is that if a symmetry is emergent, one should look for small violations of this symmetry because the underlying fundamental…
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 present an updated review of Lorentz invariance tests in Effective field theories (EFT) in the matter as well as in the gravity sector. After a general discussion of the role of Lorentz invariance and a derivation of its transformations…
As a basic symmetry of Einstein's theory of special relativity, Lorentz invariance has withstood very strict tests. But there are still motivations for such tests. Firstly, many theories of quantum gravity suggest violations of Lorentz…
Lorentz invariance (LI) is a foundational principle of modern physics, yet its possible violation (LIV) remains an intriguing window to physics beyond the Standard Model. While stringent constraints exist in the electromagnetic and hadronic…