Molecular Identifiability Limit

Jincheng Zhang

Published Aug 21, 2026• 0 citations

Abstract

This paper investigates the fundamental question of whether two fundamentally distinct chemical states can exist, yet remain permanently indistinguishable through any finite set of experiments. The concept of a Molecular Identifiability Limit (MIL) is proposed, defining a theoretical boundary beyond which distinguishing between such states becomes impossible. This work explores the implications of this limit, considering factors such as measurement precision, experimental design, and the inherent limitations of observable properties. The central argument is that while practical distinctions may be achievable within a defined experimental framework, a truly fundamental distinction in chemical state may exist, rendering it permanently unobservable. The paper develops a theoretical framework for understanding the MIL, emphasizing the role of information content and the constraints imposed by the nature of chemical systems. Mathematical formulations are presented to illustrate key concepts and relationships, including the Shannon entropy of observable properties and the relationship between measurement uncertainty and the potential for identification. The exploration highlights the profound implications of the MIL for our understanding of chemical identity and the limits of scientific knowledge.

DOI: 10.5281/zenodo.22038944

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