“Photon energies will cluster near 2.5 PeV: by January 1, 2036, at least one additional photon will be confirmed consistent with this value, and none will be confirmed at higher energy.”

The Standard Model imposes no intrinsic maximum photon energy, since photons are massless and can, in principle, reach arbitrarily high energies. The collision of ultra-high-energy protons produces neutral pions, which typically decay into two photons, with one photon inheriting nearly all the pion’s kinetic energy. The Planck Sphere model imposes a fundamental limit on the energy transferable to the pion, set by the rotational properties of the Planck Sphere medium, thereby establishing a maximum photon energy near 2.5 PeV. If confirmed, future observations should show photons clustering near this limit without exceeding it, providing evidence consistent with a structured, rotating Planck-scale spacetime. For a detailed explanation of the basis for this prediction, see: https://medium.com/the-planck-sphere/the-planck-sphere-prediction-of-a-maximum-photon-energy-near-2-5-pev-bbd180f94b34