Equation 2 · Part 1 · From Origins to Frontier: A History of Quantum and Condensed-Matter Systems
Symbol N
What this part means
N is a part of this expression. Its role is fixed by the surrounding article and by the operations shown in the formula.
Its job in the formula
N is a part of this expression. Its role is fixed by the surrounding article and by the operations shown in the formula.
Full expression→Symbol N→Article meaning
The passage around this formula
BCS theory gives condensed-matter physics one of its few genuinely load-bearing equations, and it is worth writing down because it exposes a real, falsifiable assumption rather than decorating the prose. In the weak-coupling limit, the transition temperature is related to the strength of the electron-phonon coupling N(0)V (density of states at the Fermi level times the pairing interaction) and the characteristic phonon energy (the Debye frequency) by:
Learn the underlying idea
A function assigns an output to each allowed input. The expression f(x) means “apply f to x”.
Open the illustrated functions: inputs become outputs guide →
See this notation across published equations →
Sources cited in the article section
- [2] Theory of Superconductivity ↗
- [3] July 1957: Bardeen, Cooper, and Schrieffer submit their paper, 'Theory of Superconductivity' ↗
These citations provide research context; check each source for the exact claim it supports.