High-contrast homogenization: Entry.Annealed.AveragingTransport #
Imported from the Apache-2.0 HighContrastHomogenization development at commit
7a13dbcd8d6609264a713373f5c69ceeac870472.
Integrability, lattice centering, and stationarity transport #
For the cell q = Geometry.explicitRoundedGrid jStar m, deterministic centre A, conjugator R
and
Y y = fun a => normalizedBlock (blockSub (coarseBlock (adaptedCellTranslate q j y) a) A) R,
the normalized recentred block Y y lies in L^N(S_N) for every real N ≥ 1, every generation
j and every centre y, with no membership premise beyond the standing law; at a lattice centre
adaptedCellCenter q j w of generation j_* ≤ j its entrywise mean vanishes; and the lattice
translation that moves the centre to the origin leaves its block-valued mixed norm unchanged,
‖Y z‖_{L^N(S_N)} = ‖Y 0‖_{L^N(S_N)}, with A and R held fixed. These centering, moment and
stationarity facts serve the finite-range matrix averaging lemma
l.fixed.geometry.matrix.averaging and the mean and profile estimates of the two-grid transport
p.two.grid.transport.
The cell at the origin #
adaptedCellTranslate q j 0 = adaptedCell q j. The right-hand side is
the untranslated cell; the lattice picture writes it as the translate by 0.
Integrability receipts #
The integrability receipt. Y y lies in L^N(S_N) for every real N ≥ 1, every
generation j and every centre y. No membership premise is added to any statement; this is
derived from the standing law.
The full normalized average lies in L^N(S_N) as well, through
memLqSchatten_finset_sum in the shape the class average uses.
Centering at a lattice cell #
The annealed block of a cell centred at a lattice point of the same generation is the
adapted mean. annealedBlock_adaptedCellAtCenter, moved to the adaptedCellTranslate
picture.
Centering. For a cell centred at a lattice point of generation j ≥ j_* the entrywise
mean of Y z vanishes. This is the hcent premise, in the
Matrix.of fun α β => ∫ … shape that premise uses; the same object is stated as
fun α β => ∫ …, and the two are bridged here rather than left to coincide.
Stationarity transport of the block-valued mixed norm #
The block at a lattice-centred cell is the block at the origin precomposed with the integer
translation of the coefficient field. A and R are deterministic and do not move.
Stationarity transport. ‖Y z‖_{L^N(S_N)} = ‖Y 0‖_{L^N(S_N)} for every lattice centre
z = adaptedCellCenter q j w with j_* ≤ j.
Route: adaptedCellCenter_eq_intTranslation writes the centre as an integer translation;
coarseBlock_adapted_translateCoeff turns the shifted cell into a precomposition with
translateCoeff v; IsStationaryLaw says Measure.map (translateCoeff v) P = P; and the
scalar integrand is AEStronglyMeasurable, so the change of variables for the Bochner integral
applies. This is the block-valued transport, at the block level rather than
merely entrywise.