High-contrast homogenization: Entry.Annealed.BridgeBoundarySum #
Imported from the Apache-2.0 HighContrastHomogenization development at commit
7a13dbcd8d6609264a713373f5c69ceeac870472.
The boundary sum, drift advance, and normalization sandwich #
p.successful.short.bridge. The boundary estimate retains
1-(1-γ)/8 through a separate maximum-weight inequality. Empty integer
intervals are allowed. Every inverse normalization uses a positive definite
actual annealed mean.
Removing a positive definite normalization preserves the quadratic order. The inverse is used only after its nonsingularity has been established.
A positive increment is bounded by the trace of its normalization, times the normalizer. This is the full matrix increment used in the boundary sum.
e.bridge.boundary.sum, with an explicit universal geometric constant.
This holds also for an empty generation interval and for L=0.
The actual determinant drift is nonnegative; positivity of its normalized increments is proved before reading the real sum. Empty ranges need no exception.
The printed drift advance is applied at both lengths, with the intermediate
loss controlled using nonnegative loss on [n+L,n+2L]. All constants are numerical.
The three means in the old grid share the terminal normalizer. The upper factor is the exponential of the unscaled log-determinant loss.
Both actual Whitney errors relative to the terminal old-grid mean. The
boundary decay retains 1-(1-γ)/8; the source tail is enlarged only after the
three-generation sandwich and the two drift advances have been established.