A prior note discusses the purported research breakthrough in making superconductors that operate a room temperature and pressure (”RTP superconductors”) and the associated theoretical model, which involves superconducting quantum wells forming in the material due to mechanically induced strain introduced by doping the material’s crystal lattice to replace some atoms with “larger” ones.

Beyond the significant engineering possibilities, making room-temperature-and-pressure superconductors would present interesting opportunities in theory and fundamental research. We have a partial theory for how “conventional” (non-room-temperature-and-pressure) superconductors work, but it is not clear it will properly describe RTP superconductors.

Current superconductor theory involves “Cooper pairs” of electrons interacting through the crystal lattice. The interaction, via wavelets of vibration called “phonons,” creates a “quasiparticle”, where the two electrons share the same quantum state. This forms what is called a “condensate.” Since quantum mechanics describes entities as a collection of state properties, two entities with the same properties are effectively the same entity, meaning that the two electrons “lose their identity”. This has been observed at scales up to a few hundred nanometers - long distances in atomic terms.

Quantum mechanics describes two kinds of particles - bosons, like photons, where multiple particles can be in the same state, i.e. have the same quantum parameters, and fermions, which cannot. The inability for multiple fermions to occupy the same state is known the “Pauli exclusion principle”. Bosons have even values for the quantum property called “spin”, while Fermions spin is measured in half values (1/2, 3/2, etc). Cooper pairs are pairs of electrons with opposite characteristics like spin, so that the quasi-particle formed by the pair is spin-neutral and acts like a boson.

But while Cooper pairs explain some aspects of superconductivity, superconductors maintain a voltage of exactly 0 across their electrodes - a much larger scale than the Cooper pair length. Our understanding of exactly how this happens is incomplete. Some theories suggest that superconductors are a manifestation of macroscopic coherent states.

Let’s consider a the quantum mechanics of an a normal material. We begin with individual atoms of a single type. Atoms have distinct energy levels that their electrons can occupy (their “absorption spectrum”), dictating the frequency of light photons they can absorb. This is the “quantum” part of in quantum mechanics. You might be able to heat a stone by any arbitrary amount but in the quantum world, atoms absorb and release photons - packets of energy - only at precisely defined frequencies. Should a photon of a different frequency pass, the atom simply does not react with it. As we bring atoms together, they begin to interfere with each other. Since atoms of the same element all all have same absorption spectrum, the Pauli exclusion principle forces each atom to alter its absorption spectrum slightly so as not to conflict with its neighbors - some shifting up, others down. In a bulk material the distinct absorption lines become bands. An insulator can absorb energy of many different levels. In a conductor like a metal, the interactions between electrons make them highly mobile, so charge can be moved around easily. The quantum properties of atoms dictate material properties.

Relativity and quantum information theory hold that information can propagate no faster than the speed of light. More precisely, space-time has as one of its properties a speed of information transmission, and light (electromagnetic fields) can move at that maximum speed.

When close an electric circuit with a battery powering the light, you apply a voltage differential (from the battery) to the circuit. The electromagnetic field races around the circuit at the speed of light in the material. Although the electrons do move (at a slow “drift velocity”) the electric field - and the information it carries - can move much faster. Pushing on one electron by applying a voltage causes it to push on its neighbor. Like the balls in the office desktop toy, the wave can move much faster than the electrons themselves.

Although the electric field moves faster than the electrons, it still takes some finite time to propagate. In a normal conductor, the voltage changes throughout the conductor in a measurable way as the wave propagates.

But in a superconducting wire, the entire wire remains at 0 voltage all the time at both ends. It is therefore impossible to vary its voltage. Instead the current varies.

Under this interpretation, the wavefunction describing the entire material - which is the sum of all the individual atoms, behaves as if it were a one giant atom rather than the

because the individual electrons within the material have become coherent and the entire material’s wavefunction would

The fact that a superconductor (within its superconducting range) always maintains a voltage of 0 across its electrodes raises information theoretical issues. With a normal conductor, exposing