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The Reversible Work Cost of Undoing Objective Records: A Second No-Go: Broadcast Structure Carries No Reversible Thermodynamic Cost

Thomas Mayer

Published May 31, 2026• 0 citations
Publisher

Abstract

A companion result [1] establishes that the deterministic recoverability of coherence from a system whose records have spread into an environment is xed by the root-delity of the inaccessible conditional records,
DOI
10.5281/zenodo.20470167

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This paper argues that the formation of a definite record in any physical system—whether a quantum measurement outcome or a neural decision—carries an unavoidable thermodynamic cost given by the Bennett-Landauer erasure bound: at least k_B T \ln 2 per bit of discarded branch information. The authors define a definite record operationally, without reference to observers, as a state in which a system selects one alternative from a set and renders the others inaccessible to itself, making the transition a many-to-one map on its state space. They address the central objection that decoherence is reversible by distinguishing the reversible entanglement step from the irreversible erasure step, arguing that the bound applies to the reset of the record system relative to its own accessible correlations. The framework is applied to quantum measurement and neural commitment as structural analogues rather than identical mechanisms, and the authors explicitly limit their claims: they do not derive the Second Law, explain the arrow of time, or require consciousness.
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