Open Research Questions

Prioritized unknowns driving the investigation. Each question represents a gap in our understanding of K4. Resolving any Tier 1 question would significantly narrow down possible solutions.

Tier 1: Maximum Leverage

RQ-1: What is the cipher TYPE?

Why it matters: Entire attack methodology changes. This is the single most valuable question.

Where it stands: (updated 2026-06-11) Unknown. It is non-periodic within the standard letter-for-letter reading, and NOT a simple linear recurrence keystream (orders 1-8 eliminated in-project). The 2026 program extended the negatives beyond the direct reading: post-transposition and free crib alignment campaigns (millions of configurations, matched nulls) closed clean, and the monoalphabetic + transposition + running-key composition class was shown to be mathematically undetectable at 97 characters (detection power 0.00), so it stays open as a limits-of-knowledge result. It may be position-dependent (not state-dependent) based on the K5 shared-positions inference , but this inference is unproven.

20 candidate approaches catalogued for this question in the idea-triage ledger. (Completed experiments are recorded in the elimination database, not in this counter.)

RQ-2: What is the key source / generation method?

Why it matters: Directly produces the plaintext.

Where it stands: The known keystream at crib positions is: - Vigenere: BLZCDCYYGCKAZ (pos 21-33), MUYKLGKORNA (pos 63-73) - These are NOT readable English, NOT a simple pattern, NOT linear recurrence

81 candidate approaches catalogued for this question in the idea-triage ledger. (Completed experiments are recorded in the elimination database, not in this counter.)

RQ-3: Is there a transposition layer, and what type?

Why it matters: Reduces problem from "find transposition AND substitution" to "find substitution."

Where it stands: (updated 2026-06-11) Mengenlehreuhr (480 perms) and Weltzeituhr permutations have been tested with all thematic keyword alphabets; no breakthrough. The 2026 non-direct program scored candidates after undoing the route (with Bean constraints re-derived in the route-undone frame) across 52 route reorderings, including route-outer x Quagmire-III-inner (25,272 configs, 2026-06-10): all clean null. If a transposition layer exists, it is not one of the tested families at the tested depths.

29 candidate approaches catalogued for this question in the idea-triage ledger. (Completed experiments are recorded in the elimination database, not in this counter.)

Tier 2: High Leverage

RQ-4: What is the role of "the point"?

Why it matters: Likely reveals a key parameter or structural element.

22 candidate approaches catalogued for this question in the idea-triage ledger. (Completed experiments are recorded in the elimination database, not in this counter.)

RQ-5: How do the 1986 Egypt trip and 1989 Berlin Wall connect?

Why it matters: Constrains plaintext content, may reveal key parameters.

64 candidate approaches catalogued for this question in the idea-triage ledger. (Completed experiments are recorded in the elimination database, not in this counter.)

RQ-6: What does "delivering a message" mean?

Why it matters: Constrains the expected plaintext format.

3 candidate approaches catalogued for this question in the idea-triage ledger. (Completed experiments are recorded in the elimination database, not in this counter.)

RQ-7: What does the pre-ENE segment (positions 0-20) encode?

Why it matters: May reveal a "key indicator group" or separate cipher for the header.

5 candidate approaches catalogued for this question in the idea-triage ledger. (Completed experiments are recorded in the elimination database, not in this counter.)

Tier 3: Moderate Leverage

RQ-8: Is the "change in methodology" from K3→K4 a specific technique?

5 candidate approaches catalogued for this question in the idea-triage ledger. (Completed experiments are recorded in the elimination database, not in this counter.)

RQ-10: Is there a connection to the sculpture's physical properties?

15 candidate approaches catalogued for this question in the idea-triage ledger. (Completed experiments are recorded in the elimination database, not in this counter.)

Tier 4: Background

RQ-9: What is K5 and how does it relate to K4?

Why it matters: Additional cribs, constraints on the cipher.

RQ-11: Is there meaningful structure in the known keystream?

8 candidate approaches catalogued for this question in the idea-triage ledger. (Completed experiments are recorded in the elimination database, not in this counter.)

RQ-12: Could the cipher use a non-standard alphabet (IJ merge, etc.)?

5 candidate approaches catalogued for this question in the idea-triage ledger. (Completed experiments are recorded in the elimination database, not in this counter.)

RQ-13: Is the reading direction standard (left-to-right, top-to-bottom)?

16 candidate approaches catalogued for this question in the idea-triage ledger. (Completed experiments are recorded in the elimination database, not in this counter.)