Fermi–Dirac Statistics
Definition
The rulebook for antisocial particles — electrons refuse to share a quantum state, which is why atoms have structure at all.
Technical definition
Fermions (half-integer spin) follow n = 1/(e^((E−μ)/kT) + 1); the +1 enforces Pauli exclusion — at most one particle per state.
Example
Electrons fill atomic shells one per state because of Fermi–Dirac statistics — without it every electron would collapse into the lowest orbital and chemistry wouldn't exist.
Common confusion
Fermi–Dirac versus Bose–Einstein is not about temperature — it is about spin. Integer-spin particles are bosons, half-integer are fermions, at any temperature.