“…Therefore the focus of one's quest should be the physics that can produce various extreme-high-energy particles -such as gamma ray photons, protons, heavier ions, and neutrinos -in massive volume. Motivated by this and more theoretically-oriented issues, such as black hole information (see, e.g., [1] [2] for reviews) and Firewall [3] [4], we have initiated in [5][6][7][8] the study of quantum gravitational effects as the potential agent behind certain astrophysical phenomena, including the generation of the UHECR particles.…”