CoarseBoundaryClause #
Ported from scottnarmstrong/Superdiffusion at 7f20476385d4af418f110303085ad0740c9eba46. Module imports, support namespace and local option directives adapted for Lean Pool.
The boundary Caccioppoli's parent-L² object, priced onto the frozen legs #
Nothing here imports that file, and nothing here claims the anchor or any source node.
What is proved #
‖u(·+c) − v_cc‖_{L²(□_{n+2})} , c = wellPlacedCentre x m (n+2) ,
priced onto the frozen clause's own legs. In the same-boundary-data architecture the split is a two-term triangle, not the plan's quadrangle:
‖u(·+c) − v_cc‖ ≤ ‖u − h‖_{L²(c+□_{n+2})} + ‖v_cc − h‖_{L²(□_{n+2})} ,
the second summand being exactly CoarseDatumPricing's output. The first
summand is decomposed (§2) as
‖u − h‖_{L²(cc)}
≤ ‖u − (u)_{cc}‖_{L²(cc)} + |(u−h)_{cc}| + ‖h − (h)_{cc}‖_{L²(cc)}
≤ 3^d ‖u − (u)_{W'}‖_{L²(W')} (mean-minimality + window transport)
+ S (the open scalar, threaded)
+ C(d) 3^{n+2} d 3^d ‖∇h‖_{L²(W')} , (data Poincaré on h alone)
See CoarseMeanComparison for the machine-checked record that the
mean-comparison chain bounds S by this very quantity rather than the other
way round.
References #
- ABK26, the boundary application.
1. The coordinate gradient against the ambient gradient #
A coordinate of the gradient is dominated by the ambient (sup) norm, in the
normalized L² carrier.
The coordinate sum of the datum gradient is at most d times the ambient
one.
2. The covering-cube pricing of ‖u − h‖, at the hinge #
The three legs of the parent-L² pricing, at the hinge.
The re-cut of normalizedL2On_coveringCube_sub_datum_le_meanControl: on the
boundary covering cube the L² distance between the solution and its own
boundary datum is priced by the frozen clause's leg (mean-minimality and the
window transport of section 1), the frozen leg (the proved data Poincaré on h
alone), and the open scalar S = |(u−h)_{cc}| at coefficient 1.
2. The covering-cube pricing of ‖u − h‖, modulo the scalar #
The three legs of the parent-L² pricing.
On the boundary covering cube cc = c + □_{n+2} the L² distance between the
solution and its own boundary datum is priced by two of the frozen clause's own
legs — one through mean-minimality and the window transport, the other through
the proved data Poincaré on h alone — and the open scalar S = |(u−h)_{cc}| at coefficient 1.
hmean is a conditional A obligation (the mean-comparison bound); every
other input is the anchor's own data.
3. The two-term split of the Caccioppoli's parent-L² object #
The normalized L² seminorm on an open cube is the cube L² norm.
The same-boundary-data split.
For CoarseGraining's DirichletForcedCubeSolution v on Q and any H¹
competitor utr on Q, the object the boundary Caccioppoli puts on its
right-hand side splits into the datum distance and the datum pricing's
zero-trace leg:
‖utr − v‖_{L²(Q)} ≤ ‖utr − h‖_{L²(Q)} + ‖v − h‖_{L²(Q)} .
Nothing is subtracted through the operator: h is v's own boundary datum and
the force is g on both sides.
The parent-L² pricing, composed, at the hinge.
The re-cut of normalizedL2On_coveringDifference_le_meanControl: the boundary
Caccioppoli's parent-L² object at the covering cube, priced onto the frozen
legs and the datum pricing's zero-trace leg, with the open scalar S threaded
additively at coefficient 1.
3. The scaled parent-L² object, at the hinge #
The parent-L² pricing, composed.
The boundary Caccioppoli's parent-L² object at the covering cube, priced onto
the frozen legs and the datum pricing's zero-trace leg, with the open scalar S
threaded additively at coefficient 1:
‖u(·+c) − v_cc‖_{L²(□_{n+2})}
≤ 3^d ‖u − (u)_{W'}‖_{L²(W')}
+ S
+ C_P(d) 3^{n+2} d 3^d ‖∇h‖_{L²(W')}
+ ‖v_cc − h‖_{L²(□_{n+2})} .
hutr and hvdat are exactly the two frame identities
BoundaryEnergyRebase's proof already carries (utr = u(·+c) by rfl,
v.boundaryData = h(·+c) by its own conclusion).