Related papers: Planck-scale Lorentz-symmetry test theories

Evidence on the violation of Lorentz symmetry arises from the observation of cosmic rays with energies beyond the GZK cutoff, $E_{GZK} \simeq 4 \times 10^{19} eV$, from the apparent transparency of the Universe to the propagation of high…

Constraints on possible Lorentz invariance violation (LIV) to first order in $E/M_{\rm Planck}$ for photons in the framework of effective field theory (EFT) are discussed, taking cosmological factors into account. Then, using the reported…

This talk summarizes some theoretical features and experimental implications of a general Lorentz-violating extension of the minimal SU(3) x SU(2) x U(1) standard model that allows for both CPT-even and CPT-odd effects. The theory would…

We review the main theoretical motivations and observational constraints on Planck scale suppressed violations of Lorentz invariance. After introducing the problems related to the phenomenological study of quantum gravitational effects, we…

The possibility of a modification of special relativity with an invariant energy scale playing the role of a minimum energy is explored. Consistency with the equivalence of different inertial frames is obtained by an appropriate choice of a…

Nonlinear deformations of relativistic symmetries at the Planck scale are usually addressed in terms of modified dispersion relations. We explore here an alternative route by directly deforming the two-point functions of an underlying field…

Modern experiments on neutron and allowed nuclear $\beta$ decay search for new semileptonic interactions, beyond the ``left-handed'' electroweak force. We show that ongoing and planned $\beta$-decay experiments, with isotopes at rest and in…

Motivated by ideas from quantum gravity, Lorentz invariance has undergone many stringent tests over the past decade and passed every one. Since there is no conclusive reason from quantum gravity that the symmetry \textit{must} be violated…

Several models of Quantum Gravity predict Lorentz Symmetry breaking at energy scales approaching the Planck scale (10^{19} GeV). With present photon data from the observations of distant astrophysical sources, it is possible to constrain…

Various approaches to quantum gravity suggest the possibility of violation of Lorentz symmetry at very high energies. In these cases we expect a modification at low energies of the dispersion relation of photons that contains extra powers…

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 theoretical analysis is performed of Penning-trap experiments comparing protons and antiprotons to test CPT and Lorentz symmetry through measurements of anomalous magnetic moments and charge-to-mass ratios. Possible CPT and Lorentz…

In this talk, a brief summary is given of the possibility of using neutral-kaon oscillations to bound CPT- and Lorentz-breaking parameters in an extension of the minimal standard model.

Quantum gravity is studied in a semiclassical approximation and it is found that to first order in the Planck length the effect of quantum gravity is to make the low energy effective spacetime metric energy dependent. The diffeomorphism…

Large extra dimensions lower the Planck scale to values soon accessible. Motivated by String Theory, the models of large extra dimensions predict a vast number of new effects in the energy range of the lowered Planck scale, among them the…

Stringent limits on the Myers-Pospelov timelike parameter for photons $\xi<10^{-15}$ coming from astrophysical tests suggest exploring more general preferred backgrounds, such as spacelike and lightlike. We take some steps in this…

GUT scale threshold corrections in minimal SU(5) supergravity grand unification are discussed. It is shown that predictions may be made despite uncertainties associated with the high energy scale. A bound relating the strong coupling…

The actual potential of the next generation of Gamma Ray Telescopes in improving the existing tests of an effective Quantum Gravity scale from the study of the propagation delay for gamma rays of different energies coming from a distant…

We investigate the prospects for constraining alternative theories of gravity with a typical near-term low-budget 21 cm intensity mapping experiment. We derive the 21 cm brightness temperature perturbation consistently in linear theory…

Using a \emph{gedanken} experiment providing presumably a minimal inaccuracy the uncertainty contributions to the space-time measurement are precisely evaluated for clock and mirror respectively. The resulting expression of minimal…