MesoscaleArithmetic #
Ported from scottnarmstrong/Superdiffusion at 7f20476385d4af418f110303085ad0740c9eba46. Module imports, support namespace and local option directives adapted for Lean Pool.
The real arithmetic of the unconditional response aggregation #
Source: ABK26.
This module contains the gauge-free real arithmetic of the aggregation half
of l.J.sensitivity.no.conditions: the mesoscale exponent bookkeeping, the
damping identities of the mesoscopic depth, and the single arithmetic fold that
turns the four aggregated families into the four terms of the frozen conclusion
Algsuperdiff.Frozen.Section24.responseJ_sensitivity_unconditional.
Nothing here mentions a coefficient field, a cube, a gauge or a multiscale
quantity: every statement is about plain real numbers. It is split off from
Provider.ResponseUnconditional.Aggregation purely so that each declaration
elaborates inside the default heartbeat budget.
Every declaration in this module is an internal helper for the Section 2.4 sensitivity providers.
Removing the mesoscale constant from the frozen rpow base #
The mesoscopic depth is attached to u = 1 + C₀ X, while the frozen conclusion
carries the bare base 1 + X. For C₀ ≥ 1 and an exponent in [0,1] the two
differ by the harmless factor C₀.
The mesoscale rescaling factor against the frozen base #
The mesoscale factor against the frozen rpow base. At the mesoscopic
depth H = mesoscaleDepth s (1 + C₀ X), the descendant rescaling factor
3^{2 t H} is bounded by 3 C₀ (1 + X)^{2t/(1-2s)} — the frozen base carries no
constant.
The damping identities of the mesoscopic depth #
The min bookkeeping of the fourth frozen term. At the mesoscopic depth
attached to 1 + C₀ X the damped square X² 3^{-2(1-2s)H} is bounded by a
constant multiple of min {1, X}².
The aggregation constant #
The constant produced by the aggregation, in terms of the constant C₀ of
the mesoscopic depth and the constant K of the per-cube estimate.
Equations
Instances For
The arithmetic fold into the four frozen terms #
The value term. K μ⁻¹ σ0⁻¹ 3^{2sH} λ⁻¹ ‖h‖²_{L²} is part of the second
frozen term.
The shaking term. K μ⁻¹ (μ-1)² σ0 3^{2sH} λ⁻¹ is the other part of the
second frozen term.
The Young split of the mixed gradient term. The source's step in ABK26:
μ⁻¹σ0⁻¹ λ⁻¹ ≤ ½(μ⁻²σ0⁻² + λ⁻²), after which the 3^{-2(1-s)H} damping sends
the first half to the third frozen term and the second half to the fourth.
The pure gradient term. K 3^{-2H} (3^{2sH} λ⁻¹)² ‖∇h‖² is the fourth
frozen term.
The arithmetic fold of the aggregation. The four aggregated families are bounded by the four terms of the frozen conclusion.