exotic kind of superconductor ... (quark/antiquark)QQ* "
A color superconducting phase is a state in which the quarks near the Fermi surface become correlated in Cooper pairs, which condense. In phenomenological terms, a color superconducting phase breaks some of the symmetries of the underlying theory, and has a very different spectrum of excitations and very different transport properties from the normal phase.
It is very hard to predict which pairing patterns will be favored in nature. In principle this question could be decided by a QCD calculation, since QCD is the theory that fully describes the strong interaction. In the limit of infinite density, where the strong interaction becomes weak because of asymptotic freedom, controlled calculations can be performed, and it is known that the favored phase in three-flavor quark matter is the color-flavor-locked phase. But at the densities that exist in nature these calculations are unreliable, and the only known alternative is the brute-force computational approach of lattice QCD, which unfortunately has a technical difficulty (the "sign problem") that renders it useless for calculations at high quark density and low temperature.
Quantum Chromodynamics suggests that most of what we call "matter" is not all that material, because a body is made of elementary "particles" that are almost mass-less (for example, the proton is made of two quarks, whose combined masses are about 1% of the mass of the proton, and of gluons, which are mass-less).
Nature wants a quark and an anti-quark to be as near as possible to minimize the energy required (the strong/color force increases with distance) but pinpointing an anti-quark's position next to its quark would require an infinite amount of energy (as per Heisenberg's uncertainty principle); and viceversa (the energy is minimal when the two particles are let loose in the universe, but then the strong force between them would become infinite). The compromise between these two extremes is the mass of the proton.
If a body gives off the energy L in the form of radiation, its mass diminishes by L/c². The fact that the energy withdrawn from the body becomes energy of radiation evidently makes no difference, so that we are led to the more general conclusion that
The mass of a body is a measure of its energy-content; if the energy changes by L, the mass changes in the same sense by L/9 × 1020, the energy being measured in ergs, and the mass in grammes.
It is not impossible that with bodies whose energy-content is variable to a high degree (e.g. with radium salts) the theory may be successfully put to the test.
If the theory corresponds to the facts, radiation conveys inertia between the emitting and absorbing bodies.
Einstein, footnote 2005.Noting that photons become heavy inside (electric) superconductors (or, better, that an observer inside a superconductor would perceive a photon as a massive particle), Wilczek derives the analogy that we live inside a (non-electric) superconductor into which particles (and then objects) acquire mass. That "superconductor" is made of the Higgs condensate, which is made from the Higgs particle. The rest of the review of 'The Lightness of Being', here.
Superconductivity, short.
When the pixel is hit by a photon, it disrupts Cooper pairs, releasing free electrons - referred to as "quasiparticles" in this context - which can pass through the insulating junction and are immediately swept out as a measurable current.
The superconducting photon sensors have been used in radiation counters whose spectroscopic capabilities allow them to identify particular controlled radioactive materials and not be confounded by background radiation. Arrays are also useful in astronomy, particularly in the millimeter and submillimeter regions of the electromagnetic spectrum. A wide range of other applications is also being investigated.
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