Macroscopic ground-state occupation · Tc = (ℏω/kB)(N/ζ(3))^(1/3) for harmonic trap
Bose–Einstein statistics: ⟨n_k⟩ = 1/(e^(ε_k−μ)/kT − 1). Below T_c, chemical potential μ → 0⁻ and the ground state acquires macroscopic occupation N₀ = N[1−(T/T_c)³] for a 3D harmonic trap. The momentum distribution develops a sharp condensate peak (delta function at p=0) visible against the thermal halo.