Quantum Revivals — Dispersive Wave Packet

A Gaussian wave packet spreads due to dispersion, then miraculously reassembles at the quantum revival time T_rev = 2πℏ/|E''|. Watch fractional revivals too.

Wave Packet

View

Time t0.00
T_rev
t/T_rev0.00
|ψ|² peak
Quantum Revival
For an anharmonic oscillator E_n = ωn − χn², a Gaussian packet |ψ⟩ = Σcₙ|n⟩e^{−iEₙt/ℏ}:

T_rev = π/χ — full revival
T_rev/2, T_rev/3, ... — fractional revivals (Schrödinger cats)

The packet spreads, apparently disappears, then reconstructs perfectly. This is purely quantum — no classical analog.