|Leon Cooper physics|
The quantum spin of an elementary fermion is responsible for its inability to share the quantum space of another fermion. Each fermion has its own identity; each electron buzzing about an atom is different from the other electrons. However, a moving electron distorts its surrounding ion lattice, increasing its positive charge, which attracts another electron. These paired electrons circle each other in opposite directions, with opposite spins, to move together as a team with the lattice distortion. They act as a composite boson with an integer spin, so many may condense into the same quantum state and superconduct.
The elastic relationship between an electron and the lattice it moves in, vibrating like a real particle, to some extent and purpose is one, virtual in its transience, maybe a particle, maybe a wave, may carry a force and alter behavior, in which latent energy becomes blatant.
“Phonon,” yes, I didn’t say “photon.” Think of sound instead of light, but what is a little light? What is a little vibration if you can’t put your finger on it? In this gray area, heat could be from low-energy photons or something else, or all mixed up and indistinguishable, where virtual reality becomes inextinguishable.
A Cooper pair is bound together by such a weak force that only a little thermal excitation is enough to overwhelm it.
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