Related papers: Constraints on Lorentz Invariance Violating Quantu…
Inverse-Compton cascades initiated by energetic gamma rays (E>100 GeV) enhance the GeV emission from bright, extragalactic TeV sources. The absence of this emission from bright TeV blazars has been used to constrain the intergalactic…
Time-of-flight measurements of high-energy astrophysical neutrinos can be used to probe Lorentz invariance, a pillar of modern physics. If Lorentz-invariance violation (LIV) occurs, it could cause neutrinos to slow down, with the delay…
The last years have seen a revolution in ground-based gamma-ray detectors. We can now detect the spectra of nearby TeV blazars like Mrk 421 and 501 out to approximately 20 TeV, and during the strongest flares, we can now follow fluctuations…
Gamma-ray bursts (GRBs) have been considered as potential very high-energy photon emitters due to the large amount of energy released as well as the strong magnetic fields involved in their jets. However, the detection of TeV photons is not…
On October 9, 2022, the Large High Altitude Air Shower Observatory (LHAASO) reported the observation of the very early TeV afterglow of the brightest-of-all-time GRB 221009A, recording the highest photon statistics in the TeV band ever from…
We show that the GRB 221009A spectrum detected by LHAASO can be used to probe effects of quadratic subluminal Lorentz Invariance Violation (LIV) through the enhancement of the observed flux at the highest energies. In particular, we argue…
Lorentz Invariance Violation (LIV) may be a good observational window on Quantum Gravity physics. Within last few years, all major Gamma-ray experiments have published results from the search for LIV with variable astrophysical sources:…
Motivated by experimental indications of a significant presence of heavy nuclei in the cosmic ray flux at ultra high energies ($\gtrsim 10^{19} \eV$), we consider the effects of Planck scale suppressed Lorentz Invariance Violation (LIV) on…
We discuss the problem of the absorption of very high-energy gamma-rays by pair production interactions with extragalactic photons which originate from stellar emission in the near IR-UV and reradiation of starlight in the mid- and far-IR.…
Lorentz invariance violation (LIV) in gamma rays can have multiple consequences, such as energy-dependent photon group velocity, photon instability, vacuum birefringence, and modified electromagnetic interaction. Depending on how LIV is…
GRB 221009A has posed a significant challenge to our current understanding of the mechanisms that produce TeV photons in gamma-ray bursts (GRB). On one hand, the Klein-Nishina (KN) effect of the inverse Compton scattering leads to less…
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…
The Lorentz invariance violation (LIV) predicted by some quantum gravity theories would manifest as an energy-dependent speed of light, which may potentially distort the observed temporal profile of photons from astrophysical sources at…
We set constraints on O(E/M) Lorentz Violation in QED in an effective field theory framework. A major consequence of such assumptions is the modification of the dispersion relations for electrons/positrons and photons, which in turn can…
It has been reported that the Large High Altitude Air Shower Observatory (LHAASO) observed very high energy photons from GRB 221009A, with the highest energy reaching 18~TeV. We find that observation of such high energy photons is quite…
A number of works have claimed detections of a turn-over in the spectral lag data for individual Gamma-Ray Bursts (GRBs), caused by an energy-dependent speed of light, which could be a possible manifestation of Lorentz invariance violation…
Lorentz Invariance Violation (LIV) manifesting itself by energy dependent modification of standard relativistic dispersion relation has recently attracted a considerable attention. Ellis et al. previously investigated the energy dependent…
We obtain modified dispersion relations by requiring the vanishing of determinant of inverse of modified photon propagators in Lorentz invariance violation (LIV) theory. Inspired by these dispersion relations, we give a more general…
There are observations indicating a possible anomalous transparency of intergalactic space (filled with infrared background light) for extragalactic gamma-rays of very high energy (> 100 GeV). The anomaly is usually associated with effects…
Relativistic jets from blazars are known to be sources of very-high-energy gamma rays (VHEGRs). During their propagation in the intergalactic space, VHEGRs interact with pervasive cosmological photon fields such as the extragalactic…