The "demon" particle is a quasiparticle predicted by physicist David Pines in 1956. It's a collective excitation of electrons in a solid that behaves like a massless, neutral particle . Researchers recently confirmed its existence in strontium ruthenate using advanced electron energy-loss techniques. Key Properties of the Demon Particle: - Massless: The demon particle has no mass, like a non-corporeal demonic being, allowing it to form at any energy level and temperature. - N