structure
definition
Spin
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IndisputableMonolith.QFT.SpinStatistics on GitHub at line 49.
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depends on
used by
-
D2_no_spinor_structure -
D4_no_spinor_structure -
dimension_forcing_summary -
eight_tick_forces_D3 -
HasRSSpinorStructure -
physical_eight_tick -
spinor_dim_D4 -
why_D_equals_3 -
exchange_sign_boson -
spin_statistics_certificate -
summary -
electron_is_fermion -
fermion_wavefunction_antisymmetric -
QuantumState -
boson_symmetric -
boson_symmetric_wavefunction -
boson_symmetry_from_8tick -
cyclePhase -
eight_ticks_full_cycle -
exchange_equals_rotation -
exchangePhase -
exchangeSymmetryFromSpin -
fermion_antisymmetric -
fermion_antisymmetric_wavefunction -
fermion_antisymmetry_from_8tick -
half -
halfCyclePhase -
halfInt -
int_half_exclusive -
int_or_half -
isHalfInteger -
isInteger -
no_sm_falsifier -
ofInt -
one -
phasePerTick -
spin_statistics_boson -
SpinStatisticsFalsifier -
spin_statistics_fermion -
statisticsFromSpin
formal source
46/-! ## Spin Representation -/
47
48/-- Spin quantum number as a half-integer (n/2 for integer n). -/
49structure Spin where
50 /-- Twice the spin value (to keep integer arithmetic). -/
51 twice : ℤ
52 /-- Spin must be non-negative. -/
53 nonneg : twice ≥ 0
54
55namespace Spin
56
57/-- Create a spin from an integer (s = n means spin n). -/
58def ofInt (n : ℕ) : Spin := ⟨2 * n, by omega⟩
59
60/-- Create a half-integer spin (s = n/2). -/
61def halfInt (n : ℕ) : Spin := ⟨n, by omega⟩
62
63/-- Spin 0. -/
64def zero : Spin := ofInt 0
65
66/-- Spin 1/2 (electron, quarks). -/
67def half : Spin := halfInt 1
68
69/-- Spin 1 (photon, W/Z, gluon). -/
70def one : Spin := ofInt 1
71
72/-- Spin 3/2 (hypothetical gravitino). -/
73def threeHalves : Spin := halfInt 3
74
75/-- Spin 2 (graviton). -/
76def two : Spin := ofInt 2
77
78/-- The actual spin value as a real number. -/
79noncomputable def value (s : Spin) : ℝ := s.twice / 2