Spectral Selection Hypothesis and Physical Accessibility in Algebraic Quantum Field Theory

This preprint proposes the Spectral Selection Hypothesis, a conceptual framework motivated by recurring structural patterns appearing in Algebraic Quantum Field Theory, modular theory, relative entropy, black-hole path integrals, and related areas of theoretical physics. The work does not claim new theorems or a completed physical theory. Its purpose is to identify and formulate a common research question concerning the emergence of physically accessible sectors from larger mathematical structures.