Quantum Many-Body Scarring — PXP Model

ETH violation · Tower of scar states · Neel state revivals

PXP Model Controls

PXP Hamiltonian:
H = Σᵢ Pᵢ₋₁ σˣᵢ Pᵢ₊₁
where Pᵢ = (1−nᵢ)/2 is projector onto |0⟩ (Rydberg blockade).

Scar states form a tower with equal spacing ~1.33, leading to perfect revivals of the Néel state at period T≈π/1.33.

ETH predicts all mid-spectrum states have volume-law entanglement. Scars violate this — they have area-law entanglement embedded in the thermal bulk.

Perturbation destroys perfect revival.