Ghostly Duet: Neutrino Decay of a Superluminal Photon ✦
Photons with energies a billion times higher than visible light may secretly outrun themselves and decay into neutrino pairs. It's like light casting a shadow that steals its own energy. The LHAASO telescope already catches such quanta from the Crab Nebula. Soon, we might notice photons 'going missing' — and then Lorentz invariance, the bedrock of Einstein's theory, will show its first crack.
🎯 The effective mass of a PeV photon at a typical speed shift is only about 10 keV — a hundred times lighter than an electron, yet millions of times heavier than the lightest neutrino. Due to the feebleness of the neutrino interaction, its lifetime stretches billions of years, comparable to the age of Earth. Such a long-lived photon could have existed since the planet formed, never once decaying.
🎬 Imagine a neutrino telescope capturing the shadows of photons: it predicts gamma-ray bursts before the light arrives, working as a cosmic detector of hidden symmetries.