Wigner function W(x,p) — blue=positive, red=negative
Density matrix ρ(x,x') magnitude
Quantum State
Zurek's einselection (1981): environment-induced superselection. The pointer basis consists of states robust against environmental monitoring. Off-diagonal elements of ρ (quantum coherences) decay as:
ρ(x,x') → ρ(x,x')·exp(−γ(x−x')²t)
The Wigner function interference fringes (oscillating between ±) signify quantum coherence. Decoherence destroys these fringes, leaving a classical mixture.
ρ(x,x') → ρ(x,x')·exp(−γ(x−x')²t)
The Wigner function interference fringes (oscillating between ±) signify quantum coherence. Decoherence destroys these fringes, leaving a classical mixture.