IECZ-III: Hardcore Condensation Lift with Size-Aware Invariants
Marko Lela
TL;DR
IECZ-III develops a compact, size-aware blueprint for passing structure through gadget lifts by isolating two low-order invariants—the cumulative mod-$q$ Fourier mass up to degree $k$ and the noise stability $\mathrm{Stab}_\rho$—into a reusable profile tied to the gadget’s affine interface. The framework preserves the profile exactly under coordinate permutations ($\Delta=1$) and permits degree expansion by at most a factor $\Delta$ under bounded fan-in, with all overheads explicitly tracked in a fixed $O(\log N)$ header within a balanced window $m=(1+\gamma)n$. It proves a distributional erasure-complexity (EC) lower bound in the window (via a switching-path argument and a row-distance hypothesis) and derives an “echo”: correlations against size-aware $\mathrm{AC}^0{+}\log$ and a logarithmic-degree lower bound in polynomial calculus, all connected through a reproducible, prefix-free accounting scheme. The work also offers a transferable template for hardness transfers that preserves measurable structure, supported by empirical diagnostics such as pattern-context gaps (PCG) and low-order mass/stability proxies, demonstrating alignment between analytic invariants and compression-based signals. Overall, IECZ-III provides a concrete, reusable interface for size-budgeted gadget lifts, enabling rigorous, quantifiable hardness transfers while keeping all overheads transparent and verifiable.
Abstract
This paper develops a compact, size-aware blueprint for transferring structure through gadget lifts. Two low-order invariants -- cumulative mod-$q$ Fourier mass up to degree $k$ and noise stability $\mathrm{Stab}_ρ$ -- are treated as a reusable "profile" tied to the gadget's affine interface. Under coordinate permutations ($Δ=1$) the profile is preserved exactly; under bounded fan-in the degree budget relaxes by at most $+Δk$ (i.e., $k \mapsto k + Δk$), with all overheads tracked explicitly. In a balanced window $m=(1+γ)n$ the framework yields a distributional lower bound for a monotone cost (Erasure Complexity, EC) and an "echo" to correlation against size-aware $\mathrm{AC}^0{+}\log$ and to logarithmic degree in the polynomial-calculus setting. The accounting keeps total-variation non-expansion and a single $O(\log N)$ prefix-free header visible end to end, avoiding hidden slack.
