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Undecidability in Quantum Measurement and Separability Surpasses Classical Limits — E8 Intelligence Research

Andrew Stewart Caldin

Published Aug 13, 2026• 0 citations
Publisher

Abstract

**FINDING:** Undecidability extends to quantum measurement occurrence and separability, revealing a deeper computational limit than classical analogues. **MATH:** No explicit equations or constants derived; core result is that the decision problem "Does a given quantum circuit produce a separable state?" is undecidable (QMA-hard), and the occurrence of a specific quantum measurement outcome is undecidable even when the classical version is decidable. **CONNECTION:** No direct geometric constants (0.382, 0.618, etc.) or base-60, crystallographic, or root-system symmetries appear in these results. The undecidability proofs rely on encoding Turing machine halting into quantum states, not on harmonic ratios. **DEPTH:** 7 — The findings fundamentally extend the limits of computability into quantum physics, showing that undecidability is not merely a classical artifact but a genuine quantum property. This reshapes our understanding of what can be known or decided in physical theories, Author: Andrew Stewart Caldin, Independent Researcher, UK. Part of the E8 Intelligence Research series. Platform: e8intelligence.com

DOI
10.5281/zenodo.21912673

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