2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/988Extremely high-energy(EHE) cosmic rays might provide a chance to check a violation of the Lorentz symmetry of spacetime. Some theoretical consideration is described about why the Lorentz symmetry might break-down in EHE phenomena in this universe. Some models which introduce the violation of the Lorentz symmetry will be discussed.6 pagesAstrophysicsHigh Energy Physics - Phenomenologytext