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Equation 10 · Part 1 · From Origins to Frontier: A History of Quantum and Condensed-Matter Systems

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102310^{23}
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What this part means

A raised number can be a power. When it is a label or bound, it selects a case or the upper limit of a sum; the formula’s structure distinguishes these uses.

Its job in the formula

A raised mark can be a power or an index. Its position and the surrounding notation determine which.

The passage around this formula

None of this history would be describable in ordinary language without one conceptual device: the quasiparticle. A solid contains on the order of 10^{23} interacting electrons per cubic centimeter, and no exact solution to that many-body problem exists or is expected. Lev Landau’s Fermi-liquid theory showed that in many metals, the low-energy excitations of this impossibly complex system behave, to good approximation, like a gas of weakly interacting particles carrying renormalized properties — an effective mass different from the bare electron mass, a finite lifetime, sometimes a fractional charge. A Cooper pair is a quasiparticle composite; the flat plateaus of the quantum Hall effect are…

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Learn the underlying idea

An exponent tells how a base is used in multiplication. In x³, x is the base and 3 is the exponent: x³ = x × x × x.

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The article lists its research sources here.