Carpet-3 300 TeV Photon Event as an Evidence for Lorentz Violation

The detection by the Carpet-3 Group of a 300 TeV photon, observed 4536 seconds after the prompt emission of the historic gamma-ray burst GRB 221009A, provides unprecedented opportunities to test Lorentz invariance violation (LV) at energy scales approaching the Planck regime. By analyzing the temporal and spatial properties of this ultra-high-energy photon in conjunction with lower-energy photons from other bursts and the same burst, we demonstrate consistency with subluminal LV scenarios characterized by an energy scale \( E_{\rm LV} \sim 3 \times 10^{17} \, \rm{GeV} \). This work bridges multi-year LV studies using GeV-TeV photons and establishes GRB 221009A as a pivotal laboratory for quantum spacetime phenomenology.