From margin cells to all cells in the origin A slot of prop:bootstrap #
The clipped cell estimate of prop:bootstrap for the spatial pressure gradient
is proved directly only on margin cells: cells whose centre lies in the
closure of the origin carrier of radius R₁ and whose radius is at most
(1 - R₁)/4. This file removes both restrictions, at the cost of one absolute
factor on the Calderón–Zygmund constant.
The clipped time integral of the 6/5 power of the spatial L^{6/5} slice
norm is the space-time mass of |∂ᵢp|^{6/5} over the cell clipped to the
carrier, so it is monotone in the cell. Two comparisons then suffice.
- A cell of radius at most
(1 - R₁)/8clipped to the carrier is contained in a margin cell of twice the radius centred in the carrier. Doubling the radius costs the factor2^θ ≤ 8, since the growth exponentθofprop:bootstrapis at most71/25. - A cell of radius larger than
(1 - R₁)/8is bounded by the whole clipped carrier mass, and the carrier is covered by197³ · 4611margin cells of radius exactly(1 - R₁)/8, each of which is smaller than the given radius, so the growth factor only improves.
Both costs are absolute, and the affine slot originKPAffineASlot is
superhomogeneous in |C_CZ| + 1, so both are absorbed by requiring
C_CZ ≥ originASlotLargeCellThreshold Cbase. Nothing else is assumed: the
centre of the given cell is arbitrary and its radius is arbitrary.
The Calderón–Zygmund threshold at which every clipped cell of the origin carrier inherits the margin-cell A slot: the number of margin cells used to cover the carrier, times the constant of the margin-cell estimate.
Instances For
The threshold multiplies the affine slot by the cover count.
Margin cells control every cell. Given the clipped A-slot estimate of
prop:bootstrap on margin cells at the constant Cbase, every clipped cell —
any centre, any positive radius — obeys the same estimate at any constant above
originASlotLargeCellThreshold Cbase.
The A slot of prop:bootstrap above the threshold. The clipped
component-cell estimate for every centre in Q(3/4) and every radius
0 < r ≤ R₁ follows from its margin-cell restriction — centres in the closure
of the carrier, radii at most (1 - R₁)/4 — once the Calderón–Zygmund constant
is at least originASlotLargeCellThreshold Cbase. No hypothesis on the
solution beyond those of the margin-cell estimate is used.