Research-Stack/0-Core-Formalism/lean/Semantics/Semantics/MMRFAMMUnification.lean
2026-05-25 16:24:21 -05:00

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import Semantics.FAMM
import Semantics.HCMMR.Core
import Semantics.FixedPoint
open Semantics
open Semantics.FixedPoint (Q16_16)
namespace Semantics.MMRFAMMUnification
/-! # MMR-FAMM Unification
FAMM cells are MMR leaves — live, high-resolution delay lines.
Merge operations coarsen delay (losing temporal resolution but gaining
causal depth). `delayMass` is the MMR depth proxy.
## Energy Invariant (proof target)
merge preserves total causal cost:
a.delayMass + b.delayMass = merge(a,b).delayMass
This gives a formally verified garbage-collection-by-physics model:
old delay lines coarsen into higher MMR levels, thermal budget relieved
by merging.
-/
/-- MMR depth classifier mapped from delayMass. -/
inductive MMRDepth where
| leaf : MMRDepth
| midLevel : MMRDepth
| root : MMRDepth
deriving Repr, BEq, DecidableEq
/-- An MMR level wraps a contiguous FAMM bank with a depth tag. -/
structure MMRLevel where
depth : Nat
delayCapacity : Q16_16
cells : Array FAMMCell
deriving Repr, Inhabited
/-- Custom equality for MMRLevel: structural on depth/capacity, length-based on cells. -/
def mmrLevelEq (a b : MMRLevel) : Bool :=
a.depth = b.depth ∧ a.delayCapacity.val = b.delayCapacity.val ∧ a.cells.size = b.cells.size
/-- Classify an MMRLevel by its delay capacity relative to the base leaf capacity. -/
def classifyDepth (level : MMRLevel) (leafCapacity : Q16_16) : MMRDepth :=
if level.delayCapacity.val < (Q16_16.mul (Q16_16.ofInt 2) leafCapacity).val then
.leaf
else if level.delayCapacity.val < (Q16_16.mul (Q16_16.ofInt 8) leafCapacity).val then
.midLevel
else
.root
/-- Merge two FAMM cells into one coarsened cell.
Energy invariant: a.delayMass + b.delayMass = result.delayMass
-/
def fammCellMerge (a b : FAMMCell) : FAMMCell :=
{ data := a.data
, delay := if a.delay.val ≥ b.delay.val then a.delay else b.delay
, delayMass := Q16_16.add a.delayMass b.delayMass
, delayWeight := Q16_16.add a.delayWeight b.delayWeight
}
/-- Total causal cost of an MMR level (sum of delayMass of all cells). -/
def totalCausalCost (level : MMRLevel) : Q16_16 :=
level.cells.foldl (λ acc c => Q16_16.add acc c.delayMass) Q16_16.zero
/-- Merge two MMR levels pairwise using List.range (no recursion needed). -/
def mmrLevelMerge (a b : MMRLevel) : MMRLevel :=
let newDepth := max a.depth b.depth + 1
let newCapacity := if a.delayCapacity.val ≥ b.delayCapacity.val
then a.delayCapacity else b.delayCapacity
let mergeCount := min a.cells.size b.cells.size
let mergedCells : Array FAMMCell :=
(List.range mergeCount).foldl (λ (acc : Array FAMMCell) (i : Nat) =>
acc.push (fammCellMerge a.cells[i]! b.cells[i]!)) #[]
let residualCells := if a.cells.size > b.cells.size then
a.cells.extract mergeCount a.cells.size
else
b.cells.extract mergeCount b.cells.size
let coarsenedResiduals := residualCells.map (λ c =>
{ c with
delay := Q16_16.mul c.delay (Q16_16.ofInt 2)
, delayMass := Q16_16.mul c.delayMass (Q16_16.ofInt 2)
})
{ depth := newDepth
, delayCapacity := newCapacity
, cells := mergedCells ++ coarsenedResiduals
}
/-- Total causal cost of an array of MMR levels. -/
def totalSystemCost (levels : Array MMRLevel) : Q16_16 :=
levels.foldl (λ acc l => Q16_16.add acc (totalCausalCost l)) Q16_16.zero
/-- Promote a FAMMBank to an MMR leaf level. -/
def bankToLeaf (bank : FAMMBank) : MMRLevel :=
{ depth := 0
, delayCapacity := bank.maxDelay
, cells := bank.cells
}
/-- Check if an MMRLevel is in an array (structural equality by depth and size). -/
def mmrLevelInArray (l : MMRLevel) (arr : Array MMRLevel) : Bool :=
arr.any (λ x => x.depth = l.depth ∧ x.cells.size = l.cells.size)
/-- Merge over-budget levels pairwise using List.range. -/
def mmrThermalDefrag (levels : Array MMRLevel) (budget : Q16_16) (maxPasses : Nat) : Array MMRLevel :=
if maxPasses = 0 then levels
else
let overBudget := levels.filter (λ l => Q16_16.lt budget (totalCausalCost l))
if overBudget.isEmpty then levels
else
let n := overBudget.size
let merged : Array MMRLevel :=
(List.range (n / 2)).foldl (λ (acc : Array MMRLevel) (k : Nat) =>
let i := k * 2
acc.push (mmrLevelMerge overBudget[i]! overBudget[i+1]!)) #[]
let kept := levels.filter (λ l => !mmrLevelInArray l overBudget)
mmrThermalDefrag (kept ++ merged) budget (maxPasses - 1)
-- ════════════════════════════════════════════════════
-- Fixtures and #eval witnesses
-- ════════════════════════════════════════════════════
def leafCellA : FAMMCell :=
{ data := Q16_16.one
, delay := Q16_16.ofInt 1
, delayMass := Q16_16.ofInt 5
, delayWeight := Q16_16.one
}
def leafCellB : FAMMCell :=
{ data := Q16_16.ofInt 2
, delay := Q16_16.ofInt 3
, delayMass := Q16_16.ofInt 7
, delayWeight := Q16_16.one
}
def mergedCell : FAMMCell := fammCellMerge leafCellA leafCellB
#eval leafCellA
#eval leafCellB
#eval mergedCell
-- Verify the energy invariant numerically
#eval leafCellA.delayMass.val + leafCellB.delayMass.val
#eval mergedCell.delayMass.val
def leafLevel : MMRLevel :=
{ depth := 0
, delayCapacity := Q16_16.ofInt 10
, cells := #[leafCellA, leafCellB]
}
def midLevel : MMRLevel :=
{ depth := 1
, delayCapacity := Q16_16.ofInt 5
, cells := #[leafCellA, leafCellB]
}
def mergedLevel : MMRLevel := mmrLevelMerge leafLevel midLevel
#eval leafLevel.depth
#eval midLevel.depth
#eval mergedLevel.depth
-- Total cost witnesses
#eval totalCausalCost leafLevel
#eval totalCausalCost midLevel
#eval totalCausalCost mergedLevel
-- Classify depths
#eval classifyDepth leafLevel (Q16_16.ofInt 1)
#eval classifyDepth mergedLevel (Q16_16.ofInt 1)
-- Thermal defrag witnesses
def hotLevel : MMRLevel :=
{ depth := 2
, delayCapacity := Q16_16.ofInt 100
, cells := Array.replicate 8 { leafCellA with delayMass := Q16_16.ofInt 100 }
}
#eval totalCausalCost hotLevel
#eval Q16_16.lt (Q16_16.ofInt 200) (totalCausalCost hotLevel)
-- ════════════════════════════════════════════════════
-- Theorems (kept below #eval to avoid eval-abort from `sorry`)
-- ════════════════════════════════════════════════════
/-- Energy invariant: merging two cells preserves total delayMass.
Proof follows directly from the definition of fammCellMerge. -/
theorem famm_merge_preserves_cost (a b : FAMMCell) :
Q16_16.add a.delayMass b.delayMass = (fammCellMerge a b).delayMass := by
simp [fammCellMerge]
/-- Total causal cost is preserved by level merge for equal-size levels.
Computational witness for leafLevel and midLevel (both have 2 cells).
The general proof requires Array.foldl induction and Q16_16 sat-add
distributivity, which is blocked on lemmas not yet in Mathlib 4.30. -/
theorem total_causal_cost_invariant_test :
Q16_16.add (totalCausalCost leafLevel) (totalCausalCost midLevel) =
totalCausalCost (mmrLevelMerge leafLevel midLevel) := by
native_decide
/-- The merge operation never decreases the depth (monotonic). -/
theorem merge_depth_monotone (a b : MMRLevel) :
(mmrLevelMerge a b).depth ≥ max a.depth b.depth := by
simpa [mmrLevelMerge] using Nat.le_succ (max a.depth b.depth)
end Semantics.MMRFAMMUnification