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Complexitylib.Algebraic.LowerBound.Cutwidth.Extractor.Strong.Block.Recursion.Scheduled.BoundedDepth

Finite seed and entropy bounds at fixed recursion depths #

Every scheduled extractor of depth at most sixty-four has at most 2^24 * L seed bits when its local error exponent and input logarithm fit the common width L. At depths twenty-four and sixty-four, its source entropy threshold is bounded by 2^62 * L and 2^142 * L, respectively. Together with the actual output length 2^h * L, these conservative estimates support matching the seed widths of successive extractor calls.

These constants are our arithmetic deductions from the checked scheduled construction. The recursive method is credited in Recursion.Extraction. They are intended for the alternating-extraction and flip-flop route of Chattopadhyay--Goyal--Li, Non-Malleable Extractors and Codes, with their Many Tampered Extensions, Section 6, Algorithms 1--2, https://arxiv.org/pdf/1505.00107. This module proves only finite numerical bounds, not a correlation-breaker construction or its statistical guarantee.

theorem Algebraic.Cutwidth.Extractor.scheduledBlockSeedBits_boundedDepth_le (n L E h : ℕ) (length : Nat.clog 2 (n + 1) ≤ L) (room : 64 ≤ L) (depth : h ≤ 64) (error : E ≤ L) :

A common width bounds every actual seed tuple at depth at most sixty-four.

The actual depth-twenty-four source entropy is linear in the common width.

The actual depth-sixty-four source entropy is linear in the common width.