pith. machine review for the scientific record. sign in
def

mapDelta

definition
show as:
view math explainer →
module
IndisputableMonolith.UnitMapping
domain
UnitMapping
line
31 · github
papers citing
none yet

open explainer

Generate a durable explainer page for this declaration.

open lean source

IndisputableMonolith.UnitMapping on GitHub at line 31.

browse module

All declarations in this module, on Recognition.

explainer page

Tracked in the explainer inventory; generation is lazy so crawlers do not trigger LLM jobs.

open explainer

depends on

used by

formal source

  28@[simp] def apply (f : AffineMapZ) (n : ℤ) : ℝ := f.slope * (n : ℝ) + f.offset
  29
  30/-- Map δ-subgroup to ℝ by composing the (stubbed) projection `toZ` with an affine map. -/
  31noncomputable def mapDelta (δ : ℤ) (hδ : δ ≠ 0) (f : AffineMapZ) : DeltaSub δ → ℝ :=
  32  fun p => f.slope * ((LedgerUnits.toZ δ p) : ℝ) + f.offset
  33
  34lemma mapDelta_diff (δ : ℤ) (hδ : δ ≠ 0) (f : AffineMapZ)
  35  (p q : DeltaSub δ) :
  36  mapDelta δ hδ f p - mapDelta δ hδ f q
  37    = f.slope * ((LedgerUnits.toZ δ p - LedgerUnits.toZ δ q : ℤ) : ℝ) := by
  38  classical
  39  calc
  40    mapDelta δ hδ f p - mapDelta δ hδ f q
  41        = (f.slope * (LedgerUnits.toZ δ p : ℝ) + f.offset)
  42            - (f.slope * (LedgerUnits.toZ δ q : ℝ) + f.offset) := by
  43              simp [mapDelta]
  44    _   = f.slope * (LedgerUnits.toZ δ p : ℝ)
  45            - f.slope * (LedgerUnits.toZ δ q : ℝ) := by
  46              ring
  47    _   = f.slope * ((LedgerUnits.toZ δ p : ℝ)
  48            - (LedgerUnits.toZ δ q : ℝ)) := by
  49              simpa [mul_sub]
  50    _   = f.slope * ((LedgerUnits.toZ δ p - LedgerUnits.toZ δ q : ℤ) : ℝ) := by
  51              have hcast : ((LedgerUnits.toZ δ p - LedgerUnits.toZ δ q : ℤ) : ℝ)
  52                  = (LedgerUnits.toZ δ p : ℝ) - (LedgerUnits.toZ δ q : ℝ) := by
  53                    simpa using (Int.cast_sub (LedgerUnits.toZ δ p) (LedgerUnits.toZ δ q))
  54              simpa [hcast]
  55
  56/-- Context constructors: charge (quantum `qe`) and time (τ0). -/
  57def chargeMap (qe : ℝ) : AffineMapZ := { slope := qe, offset := 0 }
  58def timeMap (U : Constants.RSUnits) : AffineMapZ := { slope := U.tau0, offset := 0 }
  59
  60/-- WIP: action mapping requires Planck-like constant. Pass it explicitly. -/
  61def actionMap (hbar : ℝ) : AffineMapZ := { slope := hbar, offset := 0 }