Bipartite entanglement entropy S = −Tr(ρ_A log ρ_A) measures quantum correlations. Area law (gapped): S ~ L^(d-1). Volume law (random): S ~ L^d. Explore different quantum states.
State Type
S = —
S_max = —
Schmidt rank: —
Entanglement Entropy
Schmidt decomp: |ψ⟩ = Σ λᵢ|aᵢ⟩|bᵢ⟩
S = −Σ λᵢ² log λᵢ²
Area law (gapped 1D): S ≤ const
Volume law (random): S ~ n/2 log 2