Characterize physically admissible local operations in AQFT

Determine which unitary operators in the local observable algebras A(O) of algebraic quantum field theory (AQFT) can be regarded as physically viable local operations localized in the spacetime region O, clarifying operational criteria that distinguish admissible unitaries from formal algebraic elements.

Background

The paper shows that local observable algebras in relativistic quantum field theory are universal embezzlers, enabling arbitrary state embezzlement via local unitaries. However, the operational meaning of "local operations" in AQFT is subtle and not fully established. Clarifying which unitaries correspond to physically implementable operations is necessary to translate the mathematical embezzlement capability into concrete, experimentally meaningful procedures.

This problem seeks a precise operational characterization within AQFT: mapping the algebraic availability of unitaries in A(O) to the subset realizable under physical constraints (e.g., localization, causality, measurement theory).