lattice-system

Legacy catalogue: Spin-1/2 operators (Tasaki §2.1)

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

Spin-1/2 operators (Tasaki §2.1)

Primary reference: Tasaki, Physics and Mathematics of Quantum Many-Body Systems, §2.1 eqs. (2.1.1), (2.1.7), (2.1.8), pp. 13-15.

Lean name Statement File
spinHalfOp{1,2,3} Ŝ^(α) := σ^(α) / 2 (Tasaki (2.1.7)) Quantum/SpinHalf.lean
pauliX_eq_two_smul_spinHalfOp1 etc. σ^(α) = 2 · Ŝ^(α) (Tasaki (2.1.8)) Quantum/SpinHalf.lean
spinHalfOp1_isHermitian etc. Ŝ^(α) is Hermitian Quantum/SpinHalf.lean
spinHalfOp1_mul_self etc. (Ŝ^(α))² = (1/4) · I Quantum/SpinHalf.lean
spinHalfOp1_anticomm_spinHalfOp2 etc. anticommutation at α ≠ β Quantum/SpinHalf.lean
spinHalfOp1_commutator_spinHalfOp2 etc. [Ŝ^(α), Ŝ^(β)] = i · Ŝ^(γ) (Tasaki (2.1.1)) Quantum/SpinHalf.lean
spinHalf_total_spin_squared Σ (Ŝ^(α))² = (3/4) · I, i.e. S(S+1) with S=1/2 Quantum/SpinHalf.lean

← Single-site Pauli operators · Catalogue · Spin-1/2 rotation operators (Tasaki §2.1 eq. (2.1.26)) →