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Testing Retro-Structural Coherence in a Block Universe: A Compression-Based Protocol

by quantumstructurator
7th Aug 2025
1 min read
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Summary

I propose an experimentally falsifiable protocol to test whether retroactive structure can be statistically detected in a classical bitstring, using only standard compression algorithms and a posterior partition. This protocol is inspired by post-determined block universe models (Stoica, Price, Wharton) and is designed to produce an empirical signal without relying on quantum measurement or wavefunction collapse.

The core idea:
A random bitstring x₀ is generated. Later, a second random bitstring g is independently generated (e.g. via QRNG or PRNG). We partition x₀ using g (i.e. split x₀ into substrings A and B depending on gᵢ = 0 or 1). We then evaluate whether this partition reduces the overall compressed length of x₀ compared to compressing A and B separately. The index:

<div align="center"><code> ISCR<sub>g</sub> = ℓ(x₀) – [ℓ(A) + ℓ(B)] </code></div>

where ℓ denotes compressed length (e.g. via LZMA or PPMd), is tested against 1000+ permutations of g. A statistically significant positive value (e.g. p < 0.01) suggests that g retroactively reveals a compressible structure in x₀, despite being generated after x₀.

The interpretation is deliberately minimal:

  • No ontological claims
  • No interaction, no feedback
  • Passive structure revelation

In a strict causal-forward world, g being independent of x₀ should yield ISCR values that fall within the null distribution of its permutations. If this is violated (as simulations suggest it may be), it could be interpreted as a signature of global retro-consistency constraints, as posited by post-determined block models.

Why I Think This Matters

  • The setup is entirely classical, testable, and falsifiable.
  • It opens a path to explore time structure without invoking quantum foundations directly.
  • It relies on compression theory, not on quantum formalism.
  • It is implementable with actual physical QRNGs (e.g. photon sources).

Request for Feedback

I would appreciate technical or conceptual feedback on the following:

  • Are there plausible loopholes or artefacts that could explain a significant ISCR<sub>g</sub> without invoking any retro-structure?
  • Is the compression approach meaningful as a proxy for descriptive entropy?
  • Can this be made more robust or generalizable?
  • Would a photon-based implementation increase its epistemic value?

I'm happy to share the full paper (with formal definitions, code, simulations, Bayesian analysis, and thermodynamic argument) if anyone is interested.