lattice-system

Legacy catalogue: Multi-body operator space (abstract lattice)

Interim authority. This lossless catalogue chunk remains authoritative for formalization status and capstone identification until Issue #5228. The version 1 JSON catalogue is still a non-authoritative prototype.

Interim catalogueSpin foundations and Tasaki Chapter 2

Multi-body operator space (abstract lattice)

Primary reference: Tasaki, Physics and Mathematics of Quantum Many-Body Systems, §2.2, pp. 21-26 (tensor-product Hilbert space and site-local operators). The lattice Λ is an arbitrary finite set with decidable equality; specializing to Λ = Fin N recovers an N-site chain.

Lean name Statement File
ManyBodyOp Λ Matrix (Λ → Fin 2) (Λ → Fin 2) ℂ Quantum/ManyBody.lean
onSite i A site-embedded operator at i : Λ Quantum/ManyBody.lean
onSite_isHermitian A.IsHermitian → (onSite i A).IsHermitian Quantum/ManyBody.lean
onSite_add, onSite_sub, onSite_zero, onSite_smul, onSite_one linearity of the site embedding and onSite i 1 = 1 Quantum/ManyBody.lean
onSite_mul_onSite_of_ne distinct-site commutation (Tasaki (2.2.6), x ≠ y, S = 1/2) Quantum/ManyBody.lean
basisVec / onSite_mulVec_basisVec tensor-product basis states and their action under site operators (Tasaki (2.2.1)/(2.2.4)) Quantum/ManyBody.lean
onSite_mul_onSite_same same-site product onSite i A · onSite i B = onSite i (A · B) (Tasaki (2.2.6), x = y) Quantum/ManyBody.lean
onSite_commutator_same same-site commutator [onSite i A, onSite i B] = onSite i [A, B] Quantum/ManyBody.lean
Matrix.IsHermitian.mul_of_commute commuting Hermitians multiply Hermitian (generic; relocated to the matrix-analysis layer in PR #4342) Math/MatrixAnalysis/HermitianSum.lean

← Time-reversal map for S = 1/2 (Tasaki §2.3) · Catalogue · Generic matrix-analysis helpers (Math/MatrixAnalysis/) →