Ultrahigh-energy photons from LHAASO as probes of Lorentz symmetry violations

Wave zone of the Hořava--Lifshitz gravity coupled to a gauge vector

“…On the other hand, astroparticle experiments by means of ultra high energy (UHE) photons coming from gamma ray burst (GRB), are exploring the Universe on the largest energy scales observed so far. Particularly, the LHAASO experiment has detected on the Earth's surface, gamma rays at the PeV energy scale [7][8][9][10][11][12]. These detections are not in agreement with those models where the photon relation dispersion is of the form ω 2 ∝ k 2 .…”

“…On the other hand, it can be shown from the constraint (2) and the T+L decomposition, that the longitudinal part of the momentum E Li of the gauge sector is zero [39,40]. Now, to infer the behavior of the remaining canonical variables ı.e., g ij and N , we need to use the second class constraints (7) and (8) together with the previous estimation on the components of the momentum π ij . The suitable combination 2H p + H N of the constraints ( 7) and ( 8) leads to ∆N B…”

“…These detections are not in agreement with those models where the photon relation dispersion is of the form ω 2 ∝ k 2 . These experiments suggest that at a certain energy scale of order of 3, 6 × 10 17 GeV, speed of propagation of the photons depends on the energy scale, hence one needs a modified dispersion relation (MDR) which implies a Lorentz invariance violation (LIV) [8]. It has been argue that this observations could be consistent with String/ M-theory inspired quantum gravity [8,13], In this work we will argue in terms of a model of anisotropic gravity, proposed by Hořava, coupled to a gauge vector, describing the electromagnetic interaction.…”

“…These experiments suggest that at a certain energy scale of order of 3, 6 × 10 17 GeV, speed of propagation of the photons depends on the energy scale, hence one needs a modified dispersion relation (MDR) which implies a Lorentz invariance violation (LIV) [8]. It has been argue that this observations could be consistent with String/ M-theory inspired quantum gravity [8,13], In this work we will argue in terms of a model of anisotropic gravity, proposed by Hořava, coupled to a gauge vector, describing the electromagnetic interaction. Since the Hořava proposal [14] and its consistent extension [15], many investigations have been devoted to corroborated the consistency of the theory as a possible candidate to describe a UV complete gravitational theory [16][17][18][19][20][21][22][23][24][25][26][27][28][29].…”

Two-body decays in deformed relativity

“…Among these proposals, a prominent role is played by the those that predict a violation or deformation of the special relativistic principles (referred as LIV and DSR scenarios, respectively) in the regime in which → 0 and G → 0, but that preserves the Planck energy scale E P = c 5 /G ≈ 1.22 × 10 19 GeV. The phenomenological opportunities of this approach range among several areas, for instance threshold effects in particle interactions [6][7][8], time delays in the arrivals of relativistic particles with different energies due to modified dispersion relations (MDRs) [9][10][11][12][13][14][15]), gravitational lensing observations [16,17], violation of CPT symmetry [18,19], etc (we refer the reader to Refs. [4,5,20] for reviews in modern searches of these effects).…”