Physical Trust at the Digital-Physical Boundary
An information-theoretic framework for verification in autonomous action systems.
A governed observation boundary.
Conceptual reference model. The report is deliberately mechanism-neutral.
claimDecision prerequisite
observationCausal evidence
appraisalDeclared assurance
authorizationPolicy outcome
CENTRAL THESIS When policy depends on a present physical distinction, authorization requires an observation path that is not reducible to the disputed digital claim.
Abstract
Digital security can establish properties of representations, credentials and computing environments. It does not, by itself, establish that the physical state presupposed by a consequential action is presently true.
This report characterizes that residual problem as the physical trust gap. It develops a mechanism-neutral framework for appraising evidence about a specified physical state through an observation path that is causally connected to the referent and adversarially distinct from the disputed digital claim.
The work formalizes observational non-identifiability, relates verification to uncertainty reduction and decision risk, separates observation from authorization, and proposes candidate assurance levels, evaluation requirements and a governance pathway for a prospective Physical Trust Assurance Standard.
Interoperable meaning, protected mechanisms.
The publication makes claim semantics, assurance boundaries and research questions inspectable while keeping implementation-specific mechanisms outside the public record. It does not claim a consensus standard, product validation or current deployment.
- IncludedFormal model of the physical trust gap
- IncludedMechanism-neutral reference architecture
- IncludedAssurance, evaluation and governance pathway
- ExcludedProtected implementation details
Cite this report
Braun, N. (2026). Physical Trust at the Digital-Physical Boundary: An Information-Theoretic Framework for Verification in Autonomous Action Systems (Version 1.0). Zenodo. https://doi.org/10.5281/zenodo.21471429