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Add lean source and binary files (part 90)
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import OAI.MathematicalPhysics.NavierStokes.ForcedComputation.Programs.ClockedExpressions
import OAI.MathematicalPhysics.NavierStokes.ShearFlows.EffectiveInterface
namespace OAI
/-! Local effective bounds for clocked expressions. Periodic field factors
have global bounds; only the explicit clock profiles use a time radius. -/
namespace ForcedComputation.ClockedExpr
open ShearFlows
open scoped ContDiff BigOperators
def bound (M : ℚ) : ClockedExpr → ℚ
| .const r => |r|
| .profile q => q.bound M
| .field _ e => e.bound
| .add e f => e.bound M + f.bound M
| .mul e f => e.bound M * f.bound M
theorem bound_nonneg (e : ClockedExpr) (M : ℚ) : 0 ≤ e.bound M := by
induction e with
| const => exact abs_nonneg _
| profile q => exact q.bound_nonneg M
| field q e => exact e.bound_nonneg
| add e f he hf => exact add_nonneg he hf
| mul e f he hf => exact mul_nonneg he hf
theorem val_bound {e : ClockedExpr} (he : e.Valid) (M : ℚ) (y : SpaceTime)
(hy : |y.1| ≤ |(M : ℝ)|) : |e.val y| ≤ (e.bound M : ℝ) := by
induction e with
| const r => simp [val, bound]
| profile q => exact q.val_bound hy
| field q e => exact e.val_bound he _
| add e f ih₁ ih₂ =>
simpa only [val, bound, Rat.cast_add] using
(abs_add_le _ _).trans (add_le_add (ih₁ he.1) (ih₂ he.2))
| mul e f ih₁ ih₂ =>
simpa only [val, bound, Rat.cast_mul, abs_mul] using
mul_le_mul (ih₁ he.1) (ih₂ he.2) (abs_nonneg _)
(Rat.cast_nonneg.mpr (e.bound_nonneg M))
def diffWord (e : ClockedExpr) : List (Fin 4) → ClockedExpr
| [] => e
| j :: α => (e.diffWord α).diff j
theorem valid_diffWord {e : ClockedExpr} (he : e.Valid) (α : List (Fin 4)) :
(e.diffWord α).Valid := by
induction α with
| nil => exact he
| cons j α ih => exact valid_diff ih j
noncomputable def scalarMixed (f : SpaceTime → ℝ) : List (Fin 4) → SpaceTime → ℝ :=
List.rec f (fun j _ g y => fderiv ℝ g y (spaceTimeDirection j))
theorem val_diffWord {e : ClockedExpr} (he : e.Valid) (α : List (Fin 4)) :
(e.diffWord α).val = scalarMixed e.val α := by
induction α with
| nil => rfl
| cons j α ih =>
funext y
change ((e.diffWord α).diff j).val y = _
rw [val_diff (valid_diffWord he α), ih]
rfl
theorem mixed_bound {e : ClockedExpr} (he : e.Valid) (α : List (Fin 4))
(M : ℚ) (y : SpaceTime) (hy : |y.1| ≤ |(M : ℝ)|) :
|scalarMixed e.val α y| ≤ ((e.diffWord α).bound M : ℝ) := by
rw [← val_diffWord he α]
exact val_bound (valid_diffWord he α) M y hy
end ForcedComputation.ClockedExpr
end OAI